The tomb tower known as Halifet Gazi Türbesi is located in Amasya on the south bank of the Yeşilırmak, some 300 meters up the road to the east from the Gökmedrese. Its precise date of construction is not known, but several facts suggest that it was constructed in the twelfth century/sixth century AH. First, it is built on the site of a Byzantine church that was converted to a madrasa by the Danishmandids during their rule in Amasya (r. ca. 1097-1175/490-573 AH). Second, its association with the figure Halifet Gazi (Khalifa Ghazi), the son of two Christian converts to Islam mentioned in the Danishmandnama, suggest affiliation with the same twelfth-century dynasty. An inscription dated to 1209-1210/606 attributes the foundation of the madrasa to a Mubariz al-Din Khalif Alp ibn Tusi, a Seljuk amir, but this may have been added after construction and thus serves as a terminus ante quem for the building.1

Today, the tomb tower is the only portion of what was once a bigger complex that survives intact. It is an octagonal structure made of stone surmounted by a pointed conical roof. Each side of the octagon is approximately three meters wide. The entrance portal to the tomb is on its south side, which is distinguished by its decorative carvings, described below. Double windows with pointed arches pierce the south and southeast sides of the tower at the clerestory level. A large window at ground level opens on the east side of the tower.

On the west side of the tower, the remnants of the facade of the madrasa to which this tomb was affixed are still visible. They consist of an arcade made of baked bricks and part of a stone wall. These most likely formed part of the Byzantine church that occupied the site before Danishmandid rule of Amasya and the conversion of the church into a madrasa. 

The interior of the tomb tower is an octagonal room with a sarcophagus placed at the center. The sarcophagus is an early Christian artifact and is an example of spoliation. Early travelers to the madrasa describe the re-use of Byzantine marble slabs in the madrasa a well.2

On the building's southern facade, which extends several feet beyond the angles of the octagonal tower behind it, a series of intricate carvings frame the tom's main doorway. The doorway itself is surmounted by an arch formed by three stones. These are carved with a zig-zag border and vegetal motifs. Above this is an ornamental hood in the form of a lobed niche whose lobes are articulated with muqarnas. The stones on the niche's interior bear split-palmette motifs. The pointed niche is framed by a spiraling vine scrolls, then a strapwork border, and finally by a pseudo(?)-inscription in foliated Kufic. The door and its hood are all framed by a large, complex zig-zag pattern, then a fat band of geometric ornament based on a star-and-polygon pattern, and finally by another complex zig-zag motif.

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