This Caravanserai is located 67 Km away from the main road that connects Yazd to Kerman and is known to be one of the many Caravanserais that was built by the order of the Safavid King Shah Abbas. The place is known for its circular plan with about 1500 m2 of total area. The circular plan was used in the places facing the threat of Sand Storm. Zein-o-Din has a gate in the south part of the construct and five watch towers, one is placed against the gate, in the north side, two on the West and two on the East. The towers are built in form of semi-circles and placed 20 meters from each other. The Caravanserai has different sections such as the Shah-Neshin (Royal Section), Stable, Yards, and Hojreh (rooms).
The main yard of the caravanserai, the one placed in the center of the construct is a Dodecagon surrounded by the rooms. The Shah Neshin, which is the biggest and most luxurious rooms of the caravanserai, is placed in the northern side of the courtyard. This room has a Badgir (wind catcher) that is used to cool the room and other sections of the caravanserai. The Hojreh or rooms are octagonal construct with small square shaped Iwans in front of them and walls that are filled with niches. The only way of entering the room is via the door that opens to the courtyard and unlike the rooms in traditional houses of Iran, these rooms are not linked to each other.
The roof is covered with bricks, there are 43 guarding sections placed in the circular roof of the place. The caravanserai is mostly built of brick, plaster, lime and tile. There are also some sections that massive rocks were used as a form of foundation. As it was mentioned, the caravanserai most likely dates back to the Shah Abbas time and was made around 1587 to 1628. Together with Zizeh Caravanserai in Kashan, they make the only two circular caravanserai of Iran.