The Kharraqan towers (as known as the Kharrakhan or Kharaghan towers) are a pair of mausolea built in 1067 and 1093, in the Kharraqan region of northern Iran, near Qazvin. They are notable for being an early example of geometric ornament, an early example of double domes, and one of the earlier tomb towers that appeared in Seljuq Iran during the 11th century. The octagonal brick structures stand tall, and each side is wide. The surface of both mausolea demonstrate extensive use of geometry. The interior walls of the older mausoleum are decorated with paintings of various subjects. The eastern tower dates from 1067–68, and the western tower dates from 1093. These towers are remnant examples of architecture that existed during the Seljuk period of medieval Persia. Descriptions Structure Both mausolea have double shells for the domes; the inner shells are intact, but the outer shells on both towers are lost. There is no direct access to light through the windows on the outer and inner shells of the dome. However, the opposite positions of the window on the two shells allow indirect light into the first tower through the side window on the inner shell. Both octagonal towers have 8 rounded buttresses - one per corner. Stronach and Young speculate there were vertical ribs for the demolished outer shell of the dome; however, they conclude from the lack of same ribs in the inner side that the ridges, accompanying the ribs, were decorative. Exterior Both towers have inscriptions of their architect on the exterior surface. Muhammad b. Makki al-Zanjani is inscribed on the earlier tower; Abu’l-Ma’ali b. Makki al-Zanjani, on the later tower. Stronach and Young indicate the two names refer to the same person—a local, unknown architect. Also on the exterior of the buildings is an intricate geometric patterning formed of carved bricks. The brick also features lengthy inscriptions, both historical and Quranic. The historical inscription on the Eastern tower includes not only the architect, but also another name, possibly the mausoleum's intended patron, which can only be partially read due to damage. The Kufic inscription of Quranic text on the exterior walls of both towers, identically distributed across sides and buttresses, features Sura 59, verses 21-23, recognizable despite damage on buttresses. Samuel Stern asserts that these Suras are an unusual choice for mausolea, but points to the preceding verses as being more fitting. Parts of the inscriptions