According to the information on its inscription, the Sinason Ulu Mosque was built in 1601; however, the exact date of construction is not known. The structure is recorded in the Asar-ı Atika Register of the Central Town of the Niğde Sanjak as having been commissioned by El-Hac İbrahim.
The mosque was built using the rubble masonry technique and features a gabled roof and a rectangular plan. The prayer hall consists of two bays covered by pointed barrel vaults, while a winter room with a barrel vault is located on the eastern side. To the north of the sanctuary are two separate gallery levels. Inside, the marble mihrab and stone minbar are particularly noteworthy.
The structure has two minarets. The first is the pavilion minaret, located at the southeast corner of the sanctuary, and is considered one of the mosque’s distinctive features. The minaret is accessed from the outside via a straight staircase and features a circular upper roof surrounded by pointed arches resting on four columns. Above this sits a hexagonal cubic dome crowned with a horizontal crescent finial. Such minarets are also referred to as “minbar minarets” due to their resemblance to a minbar, and examples can be found in many mosques built in the Cappadocia region, particularly in the 19th century. The mosque’s second minaret, however, is a modern structure added in 1976.