The Kharraqan towers are mausoleums , built in 1067 and 1093 , located on the plains in northern Iran , near Qazvin .
The brick structures stand 15 metres (49 ft) tall and 4 metres (13 ft) wide , and make extensive use of geometry . Inside the older mausoleum there is a lamp and paintings .
The eastern tower dates from 1067-68 , while the western tower dates from 1093 . Both towers appear to be the work of the architect , Muhammad bin Makki al-Zanjani . It is believed that the occupant of the eastern tower was Abu Sa'id Bijar and the occupant of the western tower was Abu Mansur Iltayti .
These towers are remnant examples of architecture that existed during the Seljuk period of medieval Persia .
Both towers were significantly damaged by the 2002 Bou'in-Zahra earthquake . They were in a good state of preservation before the event , suggesting it was one of the most powerful quakes in the region for approximately 900 years .