Iranian Architecture | Persepolis
Comparison of Proportions of the Gateway and Plan of Darius's Palace
The famous Hall of Hundred Columns, which will be referred to again in this article. Five rows of ten soldiers each can be observed with the king's throne above their heads. It seemed to me that the repetition of the number 10 in the relief, matching the number of columns in this hall, and the use of multiples of ten in decorative elements surely had a deliberate purpose and that this number was likely used elsewhere, for example in the dimensioning of the building. Subsequent studies proved this theory and other more important points, some of which are explained in this article. These studies did not continue because I was living abroad and lacked the possibility of further investigation. Some time ago, one of my students named Hossein Hassanzadeh volunteered to verify the accuracy or inaccuracy of the information and measurements. I sought help from various individuals, especially Mr. Hamidreza Mehrali, a student at Isfahan Azad University, and realized that some points were wrong, as was natural and expected. About six months ago, I asked Ms. Pamela Karimi, a doctoral student in architecture, to help me with this. The main problem was the significant discrepancy between existing sources regarding information and measurements. Ms. Karimi very carefully compared the sources and available information. Although some of the main dimensions have been verified on site, a complete and new survey of the Hall of Hundred Columns was beyond our capability. In any case, all maps and information from various researchers, from Pascal Coste to Eric Schmidt and
Giuseppe Zander and Michael Roaf, were carefully compared. In this work, some initial theories were rejected and some new theories were added. What is presented in this article is not a definitive and complete verdict on the system of proportions and measurements in the Hall of Hundred Columns. Such an achievement, given the absence of first-hand written historical documents, currently seems impossible. In any case, what has been discovered, although insignificant and small compared to the engineering knowledge of the Achaemenid Iranians, is worthy of attention. These findings, which are a mere handful from a granary, demonstrate that Achaemenid architects were familiar with engineering techniques and possessed complete rules for design and site implementation.
Given the existence of metrological (measurement) relationships in the plan, confirmed by the discovery of marks carved on stone, one can confidently state that Achaemenid designs were not primitive. Beyond the axes of columns and walls, which are used in any primitive design, the thickness of walls and column bases was also predetermined. Comparison of vertical and horizontal dimensions indicates the existence of specific relationships between the height of columns and gateways and even their components with dimensions present in the plan. The Achaemenids, in addition to using specific measurement units, used the column base height and wall dimensions as a fixed module — a basis for design — in their plans. The number of times a module is repeated in the plan or in columns and gateways has a specific relationship to ancient sacred concepts and the carved motifs in the building. Beyond numerical proportions and metrological relationships, geometric relationships were also employed in designing building components.
History and Reasons for Building the Hall of Hundred Columns
The Hall of Hundred Columns, or Throne Hall, is located at the eastern extremity of the Persepolis terrace. Its name derives from the 100 columns within it. The date of its construction is estimated between 450 and 470 BC. Herzfeld in the 1930s found a stone tablet among the debris in the southeast corner of the Hall of Hundred Columns bearing an inscription in Babylonian. Based on this document, construction of the building was begun by Xerxes and subsequently his son Artaxerxes completed it. According to the theories of Eric Schmidt, the building — whose main hall covers 3700 square meters — was built for displaying the royal treasuries. Archaeological studies show that in the treasury building, during the Achaemenid period, repairs were made to allocate the courtyard and every other available space to goods storage. Documents found also prove that valuable objects were piled to the ceilings of the warehouses and even the treasury's administrative offices had been converted to storage. Given the building's typology — that the central hall is surrounded by a corridor and has no windows to the outside — it is surmised that this hall was the place for keeping and displaying the most valuable and interesting objects of the royal treasury, thereby also reducing the overcrowding of warehouses. Abundant ash found on the hall floor shows that the hall was full of combustible objects. However, given the possibility that the central section or main hall was taller than the surrounding corridors and that there were light openings in the gap between the walls and the ceiling, and that no trace of hinges or pivots has been found, the building was certainly doorless. This theory seems somewhat doubtful. In the author's view, given that the porch is on the axis of the gateway and in the path of ceremonial procession, the hall may have served, in addition to keeping some valuable objects and furniture, as a venue for grand ceremonial banquets.
Dimensions and Measurements
Michael Roaf, in an article titled Persepolis Metrology, points to important observations about measurement marks in the palaces of Darius and Xerxes. In these studies, the archaeological observations of Giuseppe Zander, who for the first time in the book Restoration Works of Historical Buildings in Iran drew attention to the existence of these marks and their relationship to the main lines of the plan, were utilized.
Rectangular marks are aligned with wall edges, T-shaped marks with wall axes, and circles with the centers of palace columns. Based on the distances between marks, Roaf proposes a measurement system as follows: cubit 57.2 to 58 centimeters, foot 34.87 to 34.88 centimeters, palm 8.7 centimeters, and finger 2.27 centimeters.
Although such marks have not been discovered in the Hall of Hundred Columns, due to the existence of specific numerical coefficients in the distances between edges and axes of walls and also in the centers of columns, the existence of specific dimensioning rules seems certain.
The distance between columns, which is generally an important dimension in designing a columned building, equals 625 centimeters in the Hall of Hundred Columns. Based on Roaf's proposed units, this amount equals 18 feet. On the other hand, we know that 18 was an important number, and the column bases of this hall have 36 (2x18) flutes.
The height of column bases and wall plinths and gateways is 96 centimeters. According to Kerfter, one of the larger Achaemenid measurement units called the Royal Cubit equals 96 centimeters. Our studies show this amount was one of the building's dimensioning modules. In this respect, a fundamental difference with classical architecture exists: in classical architecture, the column diameter at the base was the design basis. In any case, the building's length is 96 meters or exactly one hundred units. The use of the coefficient 100 cannot be coincidental. In one of the entrance gateways of the north side facing the porch, we see the king seated on his throne with five attendants before and behind him. Below the king's feet, five rows of ten Median and Persian soldiers are visible. The wall thickness of the eastern, western and northern fronts equals ten units (Royal Cubits). The distance between two base edges is 9.76 meters, which equals five units (the column base diameter is 0.75 of a unit). The numbers 10, 5 and 100 held special importance in ancient religions.
They enjoyed special significance: the tenth of Bahman is the day of the Fire Festival, which is one of the important ceremonies. Bahram, according to tradition, has 10 manifestations or forms, and Zahhak sacrificed 100 horses for Anahita. In the battle between Tishtar and Apaosha, Ahura Mazda sacrifices himself for Tishtar so that the power of ten horses, ten camels, ten bulls, ten mountains and ten rivers (totaling 50) is breathed into Tishtar.
Modular Grid in the Plan
Based on Roaf's studies and the realization that wall axes, column axes and wall corners correspond to specific lines, the idea formed in our minds that the building plan may have emerged from the superimposition of more than one grid. Subsequent studies proved this hypothesis. A chess-board grid passing through column centers determines the exact location of niches and the eastern and western gateways, which are positioned precisely on the central axis of column spans.
Another grid, with each unit equal to the height of a full column (17.40 meters), determines the edge of the middle walls and the location of the southern and northern gateways. It should be noted that if the height of one column is taken as the unit, the hall dimensions are 6x6.
Notes and Sources:
The only evidence regarding the use of geometric drawings in designing building components are marks that probably remained on stones from the use of tools such as compasses and plumb lines. In any case, in the design of gateways, a specific geometric system for designing and laying out the plan in the workshop very likely existed. It should be recalled that in the absence of advanced engineering equipment in the past, the use of simple geometric drawings executable with string and plumb line made the task of laying out plans easier, and for this reason in ancient architectures, architectural elements and designs often emerged from a series of specific and repeatable geometric drawings. In the image below, geometric drawings that we believe formed the basis for determining gateway dimensions can be seen.
As also stated in the introduction, the geometric and numerical relationships observed in the Hall of Hundred Columns and in other buildings at Persepolis are numerous, but their complete codification requires more extensive studies.
1. Roaf, Michael, Persepolis Metrology, in: Iran, V. 16, 1978, page: 67-78 2. Roaf, Michael, Sculptures and sculptors at Persepolis, Iran, Volume XXI, The British Institute of Persian Studies, London, 1983 3. Schmidt, E. F., Persepolis, University of Chicago, Oriental Institute publications, 1953 4. Zander, Giuseppe, Travaux de Restauration de Monuments Historiques en Iran, IsMEO, Rome, 1968
