During the brief reign of the Ak Koyunlu Turkomen in Hasankeyf in the late fifteenth century, the city was chosen for the kümbet (tomb) of Zeynel Bey, the eldest son of Uzun Hasan. The tomb is on the north bank of the Tigris across from the city.
Zeynel Bey died in battle in 1473, and was buried in a circular brick kümbet glazed with navy blue and turquoise tiles built by architect Pir Hasan. The building is a cylinder of diagonal patterns made using brick and tile, with a pointed arch portal doorway on the north and a window in the south wall. Above the main shaft is a slightly smaller diameter shaft, which has small windows in each of the cardinal directions an carries a hemispherical dome.
Inside the plan is octagonal, with muqarnas niches supporting the transition to the round base of the dome. Each of the eight walls has a rectangular arched niche, and the burial chamber is recessed into the floor.
Aslanapa, Oktay. Turkish art and architecture. New York: Praeger Publishers, 1971.
Sinclair, T. A. Eastern Turkey: an architectural and archaeological survey. London: Pindar Press, 1989.