Book Section: CHAPTER III—Unveiling the Open and Hidden Functions of the Mysterious North Dome of Isfahan: How Omar Khayyam Designed, for His Commissioned Projects of Solar Calendar Reform and Building Its Astronomical Observatory, Iran’s Most Beautiful Dual-Use Structure for the Annual Celebration of Nowrooz — by Mohammad H. Tamdgidi


This essay titled “Unveiling the Open and Hidden Functions of the Mysterious North Dome of Isfahan: How Omar Khayyam Designed, for His Commissioned Projects of Solar Calendar Reform and Building Its Astronomical Observatory, Iran’s Most Beautiful Dual-Use Structure for the Annual Celebration of Nowrooz” is the third chapter of the book Khayyami Art: The Art of Poetic Secrecy for a Lasting Existence: Tracing the Robaiyat in Nowrooznameh, Isfahan’s North Dome, and Other Poems of Omar Khayyam, and Solving the Riddle of His Robaiyat Attributability, which is the seventh volume of the twelve-book series Omar Khayyam’s Secret: Hermeneutics of the Robaiyat in Quantum Sociological Imagination, authored by Mohammad H. Tamdgidi.

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This essay titled “Unveiling the Open and Hidden Functions of the Mysterious North Dome of Isfahan: How Omar Khayyam Designed, for His Commissioned Projects of Solar Calendar Reform and Building Its Astronomical Observatory, Iran’s Most Beautiful Dual-Use Structure for the Annual Celebration of Nowrooz,” is the third chapter of the book Khayyami Art: The Art of Poetic Secrecy for a Lasting Existence: Tracing the Robaiyat in Nowrooznameh, Isfahan’s North Dome, and Other Poems of Omar Khayyam, and Solving the Riddle of His Robaiyat Attributability, which is the seventh volume of the twelve-book series Omar Khayyam’s Secret: Hermeneutics of the Robaiyat in Quantum Sociological Imagination, authored by Mohammad H. Tamdgidi.

In the northern wing of Iran’s Masjed-e Jameʿ of Isfahan (meaning the congregational or comprehensive mosque, also known either as the Jomʾeh Mosque, meaning the Friday mosque, or Masjed-e ʿAtiq, meaning the ancient mosque), a nearly one thousand year old structure stands that has been described by the art and architectural historian Eric Schroeder as the most beautiful structure in Iran. Yet, to this day, its function has remained a deep mystery. 

Generally referred to as the “North Dome” (an expression Tamdgidi will adopts in this chapter for the sake of convenience) the building in the complex has been studied by many experts in Iran or abroad, each having offered their own doubtful opinions about its function, having speculated its function as having been either a royal reception chamber, a transition hall, a library, or even an astronomical observatory. But no consensus has emerged over the decades about why it was built and what its function was.

Since in recent studies of the architectural history of Islam an increasing debate has emerged regarding the attribution of the North Dome’s design to Omar Khayyam, in this Book 7 of the Omar Khayyam’s Secret series dealing with the topic of the Khayyami art, Tamdgidi devotes this chapter to an in-depth study of the North Dome, seeking a reasonable explanation for the puzzle of its function, and whether it had anything to do with the life and works of Omar Khayyam. 

The relevance of this inquiry was of course elevated when, in the earlier two chapters of this volume dedicated to the presentation, translation and a clause-by-clause textual analysis of Omar Khayyam’s Nowrooznameh, we encountered the possibility that the function of the North Dome may have had something to do with Khayyam’s work on solar calendar reform and the building of an astronomical observatory in Isfahan at the time. But Tamdgidi treats this chapter as one that can stand on its own, going over some of the material presented in the previous chapter to the extent necessary, in order to show that in fact Omar Khayyam’s unreasonably and unfairly neglected Nowrooznameh (given that until this volume, it had not even been translated into English) may actually provide the key to understanding the true function(s) of the North Dome.

In this chapter, Tamdgidi first offers a historical overview of the events preceding, during, and following Soltan Malekshah’s 20-year reign from AD 1072 to 1092. The author then revisits the key contributions Omar Khayyam’s Nowrooznameh makes to understanding what the true function of the North Dome may have been. This is followed by a critical exploration of the major studies done to date, both officially and also by various architectural historians, on the North Dome. Tamdgidi then tries to integrate the most reasonable aspects of the findings regarding the open and hidden functions of the North Dome before concluding the chapter. 

The author argues that the North Dome was not only a dual-use structure intended for the annual celebration of Nowrooz and as a part of a wider structure intended to function as an astronomical observatory, but also a structure to whose design Omar Khayyam significantly contributed for both openly official and hidden personal reasons, amid whose designs we can actually find symbolic elements that speak to the spiritual heart of the collection of Robaiyat he must have composed. In other words, for reasons to be explained, Khayyam cleverly used a rare opportunity during his stay and work in Isfahan to design a building that embodied, beyond its official functions related to solar calender reform and its needed observatory, his own philosophical and theological worldview as well as the essence of what his Robaiyat was also about.

Below, the basic findings of the chapter are summarized.

Soltan Malekshah (AD 1055-1092), who lived about 37 years, formally ascended to the Seljuk throne in AD 1072 (465 LH), with Nezam ol-Molk (AD 1018-1092) serving as his vizier. In AD 1072, Soltan Malekshah was about 17 years old, and Nezam ol-Molk, 54 years old, 37 years older than the king. Since we discovered the true date of birth of Omar Khayyam in Book 2 of the series,that is, AD 1021 (being three years younger than Nezam ol-Molk), Khayyam was in AD 1072 about 51 years old, about 34 years older than the king. Taj ol-Molk, if he was around in the court at that early stage, having been reportedly born in AD 1046 (438 LH), in AD 1072 he was about 26 years old, about half the age of either Nezam ol-Molk or Khayyam. Terkan Khatun (AD 1053-1094), Soltan Malekshah’s first wife, to be eventually supportive of Taj ol-Molk against Nezam ol-Molk, was herself about 19 years old in AD 1072. Isfahan was already being treated as a capital city since AD 1051, more so under Alp Arsalan, Soltan Malekshah’s father, since AD 1063. Soltan Malekshah, born in Isfahan, evidently treated the city as his de facto capital from AD 1072.

Having repelled challenges to the throne for about two years and somewhat stabilized, Soltan Malekshah’s court administration led by Nezam ol-Molk decided to embark in AD 1074 on an ambitious plan to reform Iran’s solar calendar to correct its seasonal cycles so that taxation would not impose untimely hardship on peasants and their lords supporting the throne, and in the Iranian calendrical context, beginning of the year was supposed to fall precisely on the first day of the spring, on Nowrooz, following the longstanding and ancient Persian tradition. For this task, accurate astronomical observation was necessary, so they had to appeal to the most qualified astronomers and scientists/scholars of their time for the purpose. Therefore, they invited a team of such learned men, led by Omar Khayyam, who arrived in Isfahan in AD 1074. They stayed and worked in the city for 18 years until AD 1092, at least.

Making astronomical observation does not happen in thin air, nor does reforming the land’s solar calendar change without official decree, but it has to be adjusted and declared amid ceremonies, celebrated on an ongoing, annual basis. They both need a place to be carried out. So, besides a broader plan of building a major mosque under his own direction, Nezam ol-Molk must have delegated (or consented to such delegation) to Taj ol-Molk the administration of building a set of other building structures dedicated to astronomical observations and an official chamber for the annual celebration of Nowrooz as an occasion of high calendrical import, both projects being intimately interrelated. In fact, the astronomical observatory and where its well-funded instruments were to be kept and used could have been accommodated in a space having a dual-use function, during the year used as a part of an astronomical observatory (not the sole space dedicated to it, but having adjacent structures, for secure maintenance of the instruments, and an open-air courtyard to which it had access), and in Nowrooz as a site for royal celebration of Nowrooz. The oculus of the North Dome itself may have been openable as needed, since at the time the connected structures would have offered easy access to its roof, when needed, by way of stairway access.

The buildings and structures for the conduct of the two projects could not have been done separately from the team work led by Khayyam. Khayyam was invited to serve as a leader of both projects, aided administratively by a younger, junior, Taj ol-Molk, half his age. Khayyam was not just a simple servant of the court. He sat beside the king at times, engaging in conversations with him, treated by him as a nadim and advisor. Khayyam also may have as well been a childhood friend of Nezam ol-Molk (born in AD 1018), given the discovery of his true birth date (AD 1021) in Book 2 of this series, so he had not just official and courtly, but also personally close acquaintance with the most powerful Persian vizier. In effect, in other words, Khayyam was invited to have what Eric Schroeder centuries later suspected for the designer of the North Dome as having had a carte blanche. 

It was Khayyam, not Taj ol-Molk, who had such an authority, not the latter giving the former such a free creative space to design the observatory-celebratory complex north of the site centuries later to become the Masjed Jāmeʿ of Isfahan. Khayyam’s royal mission allowed him to have a leading role in designing and planning the building projects, since doing so required technical specialty familiar with the intricacies of what was needed for building sites design for the projects at hand, as far as their functional compatibility with the works of observatory and cultural and celebratory requirements for calendar reform were concerned. For example, the late Turkish architectural historian Özdural’s observation that the North Dome has a remarkably accurate horizontal ground surface could have been a structural requirement for using the astronomical instruments, and to require such an attribute an astronomer’s sensibility and skills would be required.

The young Taj ol-Molk, half in age relative to Omar Khayyam, could not have been an independent authority in the project starting in AD 1074, even assuming he had any role that early in the process, nor could he have been in equal power status rivalry with Nezam ol-Molk, the latter being in the height of administrative power during much of the 18 year period. The project of North Dome could not have been initiated as a project of Taj ol-Molk. At such an early stage, he was himself just a functionary of the court under Nezam ol-Molk’s authority, perhaps a favorite of the royal court and Terkan Khatun, but still in no way in par with Nezam ol-Molk in power. If he played any role in the building projects in the northern site of the complex, it would have been subject to the technical and design guidance of Omar Khayyam as a leader of the team of the learned men tasked by royal decree to build an observatory in Isfahan to reform Iran’s solar calendar and its associated Nowrooz celebratory and declarative structures. 

So, if toward the end of the 20-year reign of Soltan Malekshah internal rivalries in his court broke into the open when Terkan Khatun tried to use Taj ol-Molk as a way of countering Nezam ol-Molk’s authority over the crisis of successorship to Soltan Malekshah’s throne, Omar Khayyam’s hard labors for 18 years may have fallen victim to the chaos, the fruits of his building projects on and around the North Dome site becoming a fodder, through its ascription to Taj ol-Molk, to hoist the portfolio of Taj ol-Molk against the accomplishment of the building of the South Dome named after Nezam ol-Molk. For all practical purposes, the North Dome was deserving of being attributed to Khayyam, but the credits due to him were usurped by Taj ol-Molk and Terkan Khatun, being at odds with Nezam ol-Molk. It was part of an observatory-celebratory complex Khayyam had been commissioned to build and develop, remaining still incomplete in parts by the time both the vizier and his soltan died in AD 1092, even though the North Dome itself had already been completed.

When Khayyam arrived in AD 1074 in Isfahan, it was not his first time visiting there. He had been there before, at least when he was a young bright student of 14-16 years of age, seeking a teacher in the already regarded as a sage Ibn Sina (Avicenna) who had set up a school in his final years in Isfahan, following lots of hardships he had gone through previously. Khayyam must have known the location of that school, and he must have been thrilled in being given an opportunity in AD 1074 to choose a location (for his twin observatory-celebratory building projects related to solar calendar reform) that was on or near the location where he had sought lessons from Avicenna around AD 1036-38, before Avicenna died. 

It was during those teaching lessons that Khayyam had conversations with him about his idea of creationist evolution later to be called by him “succession order” (سلسلة الترتيب) when recalling those early conversations in his mature treatise on “Resalat fi al-Kown wa al-Taklif” (“Treatise on the Created World and Worship Duty”). Initially, having been himself (along with Avicenna) in doubt, gradually they became convinced that there is a merit in that notion, so much so that he dedicated his last keepsake Persian treatise on the universals of existence to the succinct presentation of that thesis (one we studied thoroughly in Book 4 of this series, and continued in Book 5 where his other philosophical and theological writings were also studied). Therefore, we should not be surprised to find, in the architectural design of what was eventually built on and around the North Dome, signs and expressions of the idea of “succession order” architecturally represented as both a scholarly and a personal dedication to the memory of his teacher, Avicenna, a teacher whose works he taught and lived by, critically, throughout his life, even reading his al-Shifa on the last day of his life.

There is no question that the work in building an astronomical observatory in Isfahan had begun in AD 1074. Historians of the time and later confirmed Soltan Malekshah as having deeply funded its instruments, and they had begun to be used, since Khayyam and his team had in fact carried out their preliminary observations and drafted a scheme for the reform of the new solar calendar starting in 467 LH (AD 1074), to initiate the new calendar in about 471 LH. However, the observations required a thirty-year cycle of observing the movements of Saturn, so it still was a work in progress. Such work must have been in progress somewhere, and there is no reason to doubt that it must have been in the same wider site in which new buildings and structures were being comprehensively developed in Isfahan. 

There was no reason to build another major mosque other than the South Dome already in progress from AD 1074 or earlier, and similar work of the ideation, conception, planning, and work on the observatory and North Dome complex must have begun in AD 1074 as well. Just because the two buildings were estimated (not inscribed on the building, unless destroyed in fires later on) as completed in AD 1085-86 (for the South Dome), or as inscribed on the North Dome as completed in AD 1088-89 (though the inscribing itself may have been done after that date), does not mean the work on their design and building had not commenced from AD 1074.

There is now no doubt that the North Dome must have been attached and built adjacent to other structures, since later on remained no independent staircase access to it roof for maintenance. Besides, the open courtyard to which it was connected but later, when its use in relation to astronomical observatory was abandoned, became covered and used as interior spaces, suggests the yard could have been intended for observation activities in good weather or at day or night times. At other times, the North Dome itself could accommodate observatory work, using an openable oculus on top that is still visible but was permanently closed when such use had been abandoned. Images of astronomical observatories being built elsewhere in Europe, an image of an example of which Tamdgidi reproduced on the cover of Book 6 of this series, and can be seen in Figure III.24, indicates the interior space of that building is very much like how the space of the North Dome even exists today.

In Nowrooznameh Omar Khayyam speaks of building projects that had remained incomplete at the time Soltan Malekshah died in AD 1092. Since the North Dome itself had been reported as built by then, and since therein he reports the work on the observatory, already begun, remained incomplete, and given the adjacent structures were still in construction, likely still using wood as temporary harnesses and frameworks, then during the succession crisis that emerged before AD 1092 and continued thereafter, such temporary structures could have been subject to destruction in the fires that reportedly engulfed the area. The North Dome, however, already built strongly using bricks, survived. At the time Khayyam wrote Nowrooznameh, however, those temporary structures were already in progress, since fires that took place in 515 LH (AD 1121) happened about two years before Khayyam died in AD 1123, and he had written the literary treatise earlier, after AD 1092 and during early years following then, to encourage any of the succeeding princes (most likely Muhammad Tapar) to complete the projects left incomplete from Soltan Malekshah’s time.

Based on what has been reported and written about the measurement dimensions of the North Dome building, there should be no doubt that they are precisely constructed based on the Golden Ratio. However, the findings of the late Turkish historian Alpay Özdural are also significant and reliable, since according to his measurement using the most accurate dimensions reported by Iranian engineers about the North Dome, important dimensions of various elements of the building are also proportional to an ornamentally significant triangle Omar Khayyam undisputably introduced in his treatise on dividing a circle quadrant. In fact, Khayyam, for all practical purposes, introduced in that treatise his own version of a golden triangle, one that is also expressive of aesthetically pleasing repetitive patterns in building ornamentation and architecture. 

So, we reliably face the reality of a building in the North Dome that is unusually accurate in design, and given we readily have a team leader in Omar Khayyam living and working on the site for building observatory and Nowrooz celebratory structures in the area, and given that Khayyam’s signature, through his own verifiably discussed alternative ornamental triangle ratio, is effectively stamped on the building, there should be no doubt that the designer of the building was Omar Khayyam. The North Dome is a Khayyam-designed building and we do not even need to find an inscription on it—an existing one having been perhaps later on attributed to a junior administrator and appointee rival of Nezam ol-Molk tasked with building, rather than designing, the North Dome—to regard it as being a Khayyami work of art. Khayyam cleverly inscribed his own stamp on the very fabric of its lasting brickwork, by making its parts proportional to his own proposed ornamental triangle.

Given all the hints Khayyam shares, repeatedly, in Nowrooznameh about the learned being “clever” and “sly” in pursuing knowledge and works of art, it is likely that Khayyam used the important opportunity of the 18 years of his life in Isfahan, and the royal-decreed and vizier-supported, leadership opportunity given to him as a team leader to build solar calendar related observatory and Nowrooz celebratory structures in Isfahan, to design a set of building structures that while serving his commissioned duties, also served his own personal philosophical visions. In the spirit of a highly creative poet and philosophical logician who skillfully could convey multiple meanings through the same text, written or designed/built, Khayyam used the opportunity to build the structures on or near the very same site he had visited when young seeking lessons from Avicenna, an important topic of discussion of which had been how God’s creation of the world took place in an evolutionary way, a view that he referred to as the “succession order,” introducing it in his treatise “Resalat fi al-Kown wa al-Taklif” (“Treatise on the Created World and Worship Duty”) and further and finally elaborating on it in his keepsake Persian treatise on the universals of existence. The reason the consideration of that thesis in relation to the North Dome is relevant and important is that in many ways the interior design of the North Dome symbolically represents and expresses, in a built form, the basic notion of the succession order thesis. 

Architectural historians have expressed awe at the experience of “verticality” when standing under the ceiling of the North Dome, but they have only considered it in a one-sided way, bottom to top. In fact, there is a two-fold motion an observant can experience in the building, if one holds the Islamic creationist evolutionary vision that Khayyam (and Avicenna) must have discussed on the site decades before. 

The verticality would be better interpreted as a two-fold motion, starting from the oculus of the dome, moving down from the unity of its circular higher form of the dome, down the increasingly split and fragmenting dimensions of the upper, transitional, and lower forms from 32 to 16 to 8 and to the 4-element representing the plain square of the ground floor on which humankind stands in its furthest position down the ray of God’s creation. However, embodying the core notion of the succession order thesis, by becoming consciously aware of its position in the succession order, then the humankind represented by someone visiting the building interior, a movement back to its source can also be vertically experienced, progressively moving from the cruder 4 based numbers to 8, 16, 32, to irrational (unending) circular forms of the spheres from which humankind itself has come and through which it can ascend back, going to the source of its creation past the fixed-star studded ceiling of the North Dome to its oculus representing God. 

Khayyam’s Islamic vision of creationist evolution as discussed when young with Avicenna can therefore be found, and experienced, by a human observer standing in the building. Khayyam did not have to explain this to the builder of the structure, since as an artist, the same symbols and metaphorical elements could have a multiplicity of meanings that could justify to any builder, up to any higher authority, that the building met the “observatory” and celebratory functions it had been commissioned to fulfill. So, Khayyam’s observatory can also be imagined as an inner philosophical-theological observatory as well, artistically conveyed by the spatial form of the North Dome.

As the architectural historian Arthur Pope put it, the North Dome was built to last. This is not only evident in the highly precise and innovative way the building’s brickwork architecture is constructed and ornamented, but it can also now claim to have succeeded nearly a thousand years, having survived earthquakes, fires, and social upheavals. The designer and builders of the structure could have just ornamented it with some fanciful paintings or drawings on its surface, or used wood or other less durable material to build elaborate details more that those found on the building walls. But, it was decided to be designed and built to last, using innovative dome structure techniques, and solid walls that are ornamented in their built-in brick work. 

Under the project and design leadership of Khayyam, tasked with building a space that could accompany dual-use astronomical observations and Nowrooz celebrations for centuries to come, it was also meant to express in built form the wishes of its architect for a lasting existence. “Existence” was not for Khayyam just a passing catchword. It was the very core and center of his philosophical and theological worldview, the heart and soul of his critical theology and astronomy/astrology of human existence, and a fundamental topic of his creative and poetic works of art. Besides, not having had a child of his own, and aspiring to leave a lasting keepsake in the form of his Robaiyat and written material, the North Dome could have also served as a keepsake embodying the most central tenets of his worldview.

In Nowrooznameh we find Khayyam continually expressing and emphasizing the role of the pen in making the spirit immortal to last forever. There is no reason to doubt that he may have thought of the same in the North Dome, using the pen of designing it in the heart of Isfahan on a location used decades earlier for discussions with his teacher Avicenna. The North Dome could also serve as a way of immortalizing himself in an earthly afterlife, in the brickwork dusts of the North Dome.

The most puzzling and least understood or studied aspect of the North Dome is the pattern built into the design of its interior dome ceiling. The pattern is basically a poem transposing in multiple metaphorical ways all that Khayyam wanted to convey about the meaning of the North Dome to him and its functions relative to his worldview. Aside from the technical meaning of the pentagon as revealing, as a key, the Golden Ratio governing the precise measurements of the building, the pattern is also representative of the orbit of Venus in the sky around the Sun, as viewed from the Earth. In astrological symbolism, Venus represents the angels of love, of happiness, of music, and poetry. Choosing the orbit of that “angel” as a pattern in the ceiling, circling around the central oculus representing God, Khayyam has quintessentially expressed what the existence of the building, and of the universe, is.

 This is of course quite fitting to the celebratory function of the Nowrooz for which the building was intended, and for the outer and inner “observatory” functions Khayyam also was intending the building to fulfill. But, the five cups of presumably Wine circling the circle of the rim of the dome on which verses from the Quran are inscribed discussing creation, the heavens, and the resulting cycles of night and day, serve well to suggest that indeed the spiritual Wine-serving he narrates as constituting the beginning of the Nowrooz ceremony (as narrated in Nowrooznameh), are creatively represented in North Dome’s most important element under its ceiling. Khayyam must have been so careful with this poetic design and its being built to last that he made sure it was not just a surface ornament but built-in, using the very durable structural elements of the dome. There is no way the pattern could be eliminated from the dome, without destroying the dome itself, and that has not happened, given how the building was constructed. 

The pentagon also represents the rose, another symbolic expression of springtime, fitting to the function of the North Dome for annual celebration of Nowrooz. Of course, the rose on a ceiling has been interpreted in Western architecture as a symbolic expression of secrecy, whether Khayyam intended it as such or not. However, the way the various metaphorical elements of his poetic pattern on the ceiling is “hidden” yet apparent on it, there should be no question that Khayyam must have cleverly used the opportunity of his royal court commissioned work in Isfahan during nearly two decades to leave his lasting keepsake for his earthly afterlife. 

The Venus happily playing music and serving spiritual Wine in springtime is or must have been the core of Omar Khayyam’s Robaiyat, as evident even in his literary treatise of Nowrooznameh. Khayyam cleverly distinguishes the mundane and the spiritual wines in the subtle ornamentations of his Nowrooznameh, such that a careful reader can easily discern that a Wine promised to be served in God’s heaven cannot be one that could cause harm, to be remedied with one or another prescription. The Wine that the “priest of priest” serves in a Jamsheed Cup to the Persian king, is of a different order of being than the literal wine that may or may not be beneficial to its drinker. So, the North Dome’s rendition of Wine cups circling around the dome of the ceiling to which the Venus pours Wine must evidently be interpreted as that of the Soroush angel Khayyam names in his acclamation text to be read at the beginning of the Nowrooz celebration. The Saqi of Venus on the ceiling and Soroush of Nowrooznameh are the same and both represent, also, the core of his Robaiyat, as a Wine being served for a lasting life of joy and happiness—one that the prisoner of the wine-story in Nowrooznameh, being served to test the strange drink, finds to be a bittersweet drink that leads to his freedom from the king’s gallows, a drink that was originally gifted by a Phoenix bird, homā, who planted its seeds on the grounds of the king in appreciation for its having been liberated from the poisonous fangs of a snake.

The North Dome embodies, therefore, the Robaiyat’s essential teaching about the succession order of human descent and ascent in the creationist evolutionary path of its spiritual journey from and back to its beloved source. The North Dome is not only the embodiment in built form of Omar Khayyam’s philosophy, theology, and science, but also of his literary works of art, being itself one. It appears that Khayyam was an architect as well.

The ceiling pattern of the North Dome also represents an innovative and clever architectural playfulness using the metaphor of Khargāh, or large (in this case, rounded) tent defined as a space for happy celebrations. Khayyam must have intentionally used the metaphorical sameness of the meaning of grand tent, one readily familiar and acceptable to the Seljuks given their tent-living tradition, to also advance his own personal interest of designing a lasting built expression and embodiment of “tent” as a core meaning of his own literary pen name, itself originating (as Tamdgidi tried to show in details in Books 2 and 3 of this series) in the chart of his true birth date, one in which a dazzling array of triplicities are joined in the Samimi (Cazimi) position of Mercury in the heart of the Sun. 

Even in the design of the North Dome, as illustrated by Eric Schroeder in the formation of a grand equilateral triangle having its apex in the oculus of the dome, we have for all practical purposes a series of grand triangles going around its walls and meeting in their apex in the dome’s ceiling center. In many ways, the North Dome is also an expression of Khayyam’s own pen name as a “tent-maker” since it is basically a grand tent built to last in brickwork form. So, we have another metaphorical expression of Khayyam presented in the very structure of the North Dome as a “Khargāh” or “large tent”—a name that in fact has been used for the building down the centuries, but misunderstood and mispronounced in recent decades due to a lack of attention paid to Nowrooznameh as an important literary work by our creative tent-maker. “Khayyam” can therefore now be considered to mean, the one who designed the “Khargāh” of Isfahan, having been its “tent-maker”— Khayyam, the architect of the North Dome. Given the above, the North Dome may be what Khayyam poetically refers to as the “tavern” in whose dusts he says we should be looking for him following his passing.

Those who have visited the North Dome building, architectural historians among them, have noted the solemn feeling they experience therein particularly standing on its ground floor and its rather plain surroundings on the lower level. Others have pointed to the rich tapestry of floral ornamentation on its higher walls and inside its delicately designed structures, leading to the view of its dome bearing its pentagon pattern. In Tamdgidi’s view one does not have to choose between the sad and the happy feelings one experiences when visiting the building, since the contrast itself must have been an intended result of its design as the embodiment of a two-fold vertical motion of descent and ascent of humankind in the two-fold, successively ordered, creationist evolutionary movement from and back to God.

The person standing on the ground symbolically represents humankind’s exile from its beloved source, and a desire to seek the source again being awakened by way of visiting and experiencing the majestic verticality of the North Dome’s. In that sense, the design intention for Nowrooz celebration is fulfilled by a reflection of the sadness of the exile and the happiness of hope and desire in seeking a way back to the source of one’s created existence. For the same reason, we may imagine the same experience to be evoked by way of the delicately logical and precisely designed succession order of the individual quatrains amid a collection of Robaiyat Khayyam may have also had in the works. There is no reason not to entertain the idea that the same clever inventiveness that led Khayyam to design the Khargāh of the North Dome would not seek to reproduce the same artistic and aesthetic effect by way of a grand tent architecture of his Robaiyat collection. The sad joyfulness of the North Dome then could be paralleled with the bittersweet Wine taste of experiencing the reading of the collection of his Robaiyat in a particular logical order that stitches its quatrain parts into a tent of its whole.

The North Dome must be credited back to and named after Omar Khayyam in fairness since it is his work of art, not Taj ol-Molk’s. It is intimately related to Omar Khayyam’s 18-year life and work in Isfahan, without which both its open and its hidden functions could not be fully understood. Khayyam was not just a bystander in Isfahan as the North Dome and its adjacent structures were being conceived, planned, and built over an 18 year period. He was a leader of a team of most qualified scholars of his time to carry out a most important scientific task in Iran, reforming the solar calendar for generations to come. The task required building and operating an observatory and a space for celebrating the end result of its calculations, keeping accurate count of Nowrooz by royal decree being an indispensable part of that project. They had to take place somewhere, so building the environment for them must have been and was a part of his duties. Having a carte blanche was not something he had to beg for. He had a royal decree by the king and his most powerful vizier. Taj ol-Molk was simply an administrator of the building projects to implement designs made by Omar Khayyam leading his team. 

So, the official open functions of the North Dome and its adjacent structures involved their being used as dual-use and dedicated spaces for the observatory and for the annual royal celebration of Nowrooz. However, there were hidden functions of the North Dome, and to understand them we must interpret their designs and architecture amid an in-depth understanding of all of Khayyam’s philosophical, theological, scientific, and literary works. Having become familiar with all his works as studied in this series, we can also see how Khayyam cleverly used the opportunity granted to him to design a work of art in built form that encapsulates all of his life’s work, including and especially his Robaiyat—and he built it on or near the site of the school in which he learned his most important lessons in direct conversations with Avicenna. Therefore, aside from the North Dome being an embodiment of his works and his Robaiyat in terms of a physical expression of the succession order of his/their creationist evolutionary thesis, it also for him served as a tribute to his teacher, one whose book he was still reading on his last day. 

The tent-like architecture of the North Dome as a Khargāh is Khayyam’s work of art and the essence of the Robaiyat in built form. The “Khargāh” of the North Dome is a bittersweet embodiment of humankind’s encounter with the puzzle and majesty of universal existence. It is a place to shed sadness in favor of happiness as the ultimate purpose of creation, as transient as human experience of it may be in a brief lifetime. It is a lasting tent built by the tent-maker, one that has stood strong for a thousand years, as his Robaiyat, its possibly also tent-like meanings structure still animating our lives, including this series. For this reason, it is necessary for the appropriate urban and architectural authorities in Iran to consider returning the attribution of the North Dome back to its true designer, that is, Omar Khayyam, the credit having been unjustly taken away from him amid the succession crisis and rivalry toward the end of Soltan Malekshah’s rule and its immediate aftermath.

In Tamdgidi’s view, The International Council on Monuments and Sites (ICOMOS) has made a serious mistake in not appreciating the historical significance and value of the North Dome in particular. 

The North Dome marks where the world’s most accurate solar calendar of the time was calculated, thanks to the scientific and astronomical leadership of Omar Khayyam and his team of scholars. 

Besides, its design displays not only scientific accuracy of unprecedented precision, based on the Golden Ratio and Omar Khayyam’s own discovered Triangle as introduced in his treatise on dividing a circle quadrant, but also a depth of creative talent and playfulness with building materials that still evokes wonder in those who visit or even read about it and see its images. 

The North Dome is an embodiment of all of Khayyam’s works in philosophy, theology, science, and art, and is basically a physical embodiment of the most essential wisdom of his Robaiyat, and of course his Nowrooznameh. It is a grand tent, a Khargāh, that has lasted amid one of the most earthquake prone lands in its region. Its structure, broadly and in its most minute ornamental details have been designed and built to last, as a testament to Nowrooz as a harbinger of joy and happiness not just for Iranian and its neighboring Turkish and Arab families, but for all humankind. 

Its precision is telling of the precision of the solar calendar calculated and celebrated in its structures. It is a tribute designed by Khayyam on the site of his youthful schoolwork with Avicenna. It is the embodiment of the Robaiyat in its most beautiful expression of human sadness transitioning into the joy of experiencing its reason of existence, and understanding where we have come from and must awaken ourselves to go to. 

The North Dome is Omar Khayyam’s Robaiyat built in the lasting dusts of its brickwork. It is a poem in built form. It is the tent of the tent-maker, Khayyam. By recognizing it as a world heritage site, ICOMOS can also recognize the time and energies all architectural historians, including those from the West, have spent over many decades trying to bring to the world’s attention Khayyam’s poetry in the built form of the North Dome.

Recommended Citation

Tamdgidi, Mohammad H. 2024. “CHAPTER III—Unveiling the Open and Hidden Functions of the Mysterious North Dome of Isfahan: How Omar Khayyam Designed, for His Commissioned Projects of Solar Calendar Reform and Building Its Astronomical Observatory, Iran’s Most Beautiful Dual-Use Structure for the Annual Celebration of Nowrooz.” Pp. 367-496 in in Omar Khayyam’s Secret: Hermeneutics of the Robaiyat in Quantum Sociological Imagination: Book 7: Khayyami Art: The Art of Poetic Secrecy for a Lasting Existence: Tracing the Robaiyat in Nowrooznameh, Isfahan’s North Dome, and Other Poems of Omar Khayyam, and Solving the Riddle of His Robaiyat Attributability. (Human Architecture: Journal of the Sociology of Self-Knowledge: Vol. XX, 2024. Tayyebeh Series in East-West Research and Translation.) Belmont, MA: Okcir Press.

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