From Kashan, the road to Isfahan goes to Natanz (80 kilometres or 50 miles from Kashan) where one can visit the funerary complex of Abd al-Samad, also called the Friday Mosque. Abd al-Samad is thought to have been a disciple of the Sufi sheikh Abu Sa'id, who died in 1049. The building of the complex took several years. The oldest section is a mosque in the shape of an octagonal Seljuq pavilion which was turned into a four-eivan mosque between 1304 and 1309. The tomb itself is dated to 1307. It is a cruciform chamber with a pyramidal eight-sided roof, decorated outside with blue ceramics. Inside is a superb dome. Between 1316 and 1317, a khanehqah, or dervish monastery, was added to the southwest of the complex. Today, only its gateway still stands, richly decorated in blue ceramics.
From Natanz, it is possible to make a wide detour to the northeast along the Yazd road to pass through the villages of Ardestan and Nain. Within a very short distance, one finds a remarkable concentration of some of the oldest mosques in the country, all of which have been spared destruction or rebuilding in later styles.
These small and relatively simple buildings, completely devoid of colorful glazed tile decoration, will be of particular interest to the student of early Islamic architecture in Iran. Fifteen kilometres (9 miles) north of Ardestan is Zavareh, a village which possesses the oldest dated mosque in Iran to have been built with four eivan around a central courtyard (the mosque was finished in 1136). It is this plan which became that most frequently used for Iranian mosques, replacing the older hypostyle mosque such as the one at Nain (see below). The Zavareh mosque is small and simple in structure. Its decoration is limited to a single Kufic inscription, even the mehrab is plain. Zavareh has a second mosque, the masjed-e Pamonar, built during the Seljuq period (11 th century). It is in a bad state of preservation and only very little of the original stucco decoration remains.
The Friday Mosque at Ardestan is another of the very earliest four-eivan mosques, but unlike Zavareh it was built over an older hypostyle mosque. This small mosque is characterized by wide pillars and low vaults. The dome of the main eivan still bear traces of its very fine decoration, and the mehrab are covered in carved stucco. The remains of a Seljuq madresseh can be seen in the northwest corner.