The Aqa Buzurg (Agha Bozorg) Mosque is a mosque and madrasa located in the central part of Kashan, in the heart of its historic urban core. The complex is named for the theologian Mulla-Mahdi Naraqi II, known as Aqa Buzurg, and an inscription dates the building to 1832-1833 (1248 AH).

The building occupies a long, roughly rectangular footprint oriented northwest to southeast. A sunken courtyard built on two levels (ground level and balcony) occupies the center of the complex. The entrance to the complex is on the northwestern side, at the end of a high street lined with shops. It takes the form of an arched, domed, iwan-portal. This portal leads onto a large, domed vestibule, which overlooks the courtyard from an arched aperture placed directly across from the entrance portal. Flanking this aperture are two archways leading onto a flight of a few stairs that give onto an open roof terrace overlooking both levels of the courtyard. On either side of these two archways (to the right and left as one enters the vestibule) are two broad corridors that descend on ramps and turn at right angles, leading onto arched entrances at either end of the northwestern facade of the courtyard's upper level. 

The upper level of the courtyard is flanked on the northwest side by the roof terrace mentioned above (raised above this upper level by several feet); on the southeastern side by the facade of a monumental mosque; and on its two lateral sides (southwest and northeast) by rows of blind niches, deep enough to sit in. This level serves as a balcony overlooking the sunken ground level of the courtyard.

The ground level is accessible through flights of stairs leading onto hallways that emerge at its four corners. It has a pool at its center and is surrounded on three sides by dormitories for madrasa students. On the northwestern side, under the roof terrace and entrance pavilion, is a basement (sardab) that consists of a large open space vaulted with wide arches. Wind catchers (badgir) in the form of towers rise from this subterranean structure, flanking the entrance pavilion. 

Sources: 

Haeri, Mohammad-Reza. “KASHAN v. ARCHITECTURE (2) HISTORICAL MONUMENTS.” Encyclopaedia Iranica, XVI/1, pp. 12-21. London: Routledge, 1982-.