Style/ period: Seljuk
Building type: funerary
Building usage: mausoleum
Location: 20 kilometer from the city of Tehran, Rey
Toghrol tower is a 12th-century monument located in the city of Rey, Tehran, Iran. The 20 meter tall brick tower is the tomb of Seljuk ruler Toghrol Beg, who died in Rey in 1063. The date of the construction of this tomb tower is estimated as 1139-40. It has cylindrical chamber that is composed of 22 triangular flanges on the exterior that gives it a zigzagged-cross section. There are two entrances, one on the north and one on the south side. The roof is now missing but considering the shape of the chamber and evidence provided by other tombs, the tomb was possibly built with a conical roof. There is a spiriting staircase within the wall that gives access to the roof level and that is accessed from a doorway above the northern entrance.
The outer surface of the tomb recalls Gonbad-e-Qabus in Gorgan, whose exterior is also articulated with triangular flanges. The only difference between the two tombs, aside from their dimensions, is the placement of the flanges one after the other without any intermediary space in the mausoleum of Toghrol, thus forming a zigzagged surface. The mausoleum of Toghrol is also adorned with three bands of squarish at the top that enable the transition between jagged surface of the tower walls and the circular cornice that once supported the dome. Above the squarish, the cornice is articulated with simple brick patterns, animating the structure by changing light conditions and even it was used as a huge clock at that time and it is one of the best things in the Iranian architectures.
Both entrances to the tomb are set into arched niches with rectangular frames. The southern entrance, which is grander with a rectangular plaque that possibly contained an inscription, is identified as the main access. At the top of the tower Kufic inscriptions were originally observable.
The round interior of the chamber is unadorned in plain brick. The thickness of the walls varies from 1.75 to 2.75 meters. There have been numerous attempts to renovates this structure, the most recent and extensive one was commissioned Nasser al-Din, a Qajar ruler (1848-1896). Originally, like other monument of its time, it was capped by a conical dome which would have added to its height. The inner and outer diameters are 11 and 16 meters, respectively, the exterior shape is that of a polygon with 24 angles in its design, which is thought to contribute to the structures stability against tremors. Although the structure of the tomb has remained intact, some of more delicate features, such as the inscription have been damaged or lost. The tower is protected by Iran's cultural heritage organization.