The Great Kyz Kala, or “Maiden’s Castle,” is the largest in a group of buildings outside the west wall of Sultan Kala, which includes, the Lesser Kyz Kala, 250 meters (820 feet) to the south, the Kyz Bibi complex, approximately 300 meters (984 feet) to the north-east, and two more köshks, or fortress-like buildings, to the north. The immediate vicinity has been protected and the ground surface shows little sign of disturbance. The remains of a ruined structure of uncertain plan survive to the northeast of the main building, though these have been cut by a road.
The Greater Kyz Kala is the largest köshk in the Merv Oasis, only a little smaller than the Palace in Shahriyar Ark. Although internally in a ruinous condition, its general form and many details of the architecture are still visible. This two-story köshk, approximately aligned north-south, consists of a rectangular platform with sloping sides with corrugated walls above.
These buildings were elite rural residences, probably constructed in the 8th or 9th centuries.