In traditional Persian architecture, a dome is referred to as a gonbad (). A gonbad is often double layered, and can have many shapes, such as semi-spherical, partial spherical, onion shaped, paraboloid, polygonal conical, and circular conical. For centuries, interiors were made to simulate the celestial dome, reminding the Muslim of Man's place in the cosmos compared to God and creation. Kümbet Kümbet is the name given to Seljuq mausoleums. Kümbets are an important part of Seljuq architecture. In Turkey, Azerbaijan and Iran where the Turks set up states and ruled for centuries, there are a number of examples of such mausoleums. Particularly fashionable in the thirteenth century, these monuments, referred to in Turkish as kümbet, are a continuation of the Turkish burial customs of Central Asia. These structures are either polygonal or cylindrical in shape arid are covered with a dome. The main body of the monument rests on a cubic base, the corners of which are bevelled. In the examples built before the 16th century, the dome is covered with a conical or pyramidal spire. Most of these monuments are two storied. Concealed inside the base, half of which is below ground level, is a crypt; the latter is covered by a vault and its floor is earth. The deceased was buried in the earth. The crypt had small loop-hole windows. Most kümbet in Turkey are found in the provinces of Kayseri, Erzurum, Konya, Ahlat and Bitlis Hudavend Hatun The Kümbet of Hudavend Hatun is located in Niğde city. It was built in 1312 and was commissioned by Hudavend Hatun, daughter of the Seljuk Sultan Kilij Arslan IV, and was restored by the General Directorate of Religious Endowments (Vakiflar Genel Mudurlugu) in 1962. The tomb is made of yellow cut stone and is covered by a dome topped with an eight-faceted pyramidal crown on the exterior. Total height is 15.5 meters. White marble was used in the lintels, the arches, the inscription plaques, and the cornice of the dome. The tomb is most known for its elaborate vegetal and zoomorphic carvings. Döner Kümbet The Revolving Tomb is in the way to Talas in Kayseri. Despite its name, it does not revolve, but its cylindrical form makes it look as though it might. Built in 1276 as the final resting-place of Şah Cihan Hatun, an imperial princess, it is covered in high-relief arabesque decoration depicting animals and plants. The