Is in Ahlat Ergezen Neigbourhood, next to Seyh Necmettin Kumbet in Erzen Hatun Graveyard, the oldest
building in Ahlat. It is covered by a pyramidal roof rising in a square form.İn this regard, it is the only example of its kind.Other kumbets are always in cylindrical shape with conical hat.It was built in 1222 by Seyh Necmeddin.Although there are two inscriptions on the entrance door one of them the endowment, the other is the building inscriptions of the kumbet. As it was learned from the inscription, it contains
the waaf charter belonging to Seyh Necmeddin Havai Baba’s turbe and dervish lodges (Foundation’s Turkish;
the foundation’s proviso “May Allah have mercy on him” Seyh made this holy dome…The inhabitants of his
words are not equal and his name is Aliyuddin…Surely Allah hearing and All-knowing). According to tthe inscription it was built in hijri Ramadan an Shaban month in year 619 (gregorian:1222)Kumbet was used also as a dervish lodges of the seyh.Seyh, for he died in 1222, is understood that lived in the days of Melik Esref and Ahlat ruler İzzettin Balaban.Necmeddin Seyh Havai Baba is one of the 9 saints that were entombed in Ahlat.
Kumbet has a square small pedestal 5,17x5,18 meters dimensions, A seven step stair goes down on the northern
front of the funeral part, where can be entered the
mummy floor byan arched entry door
The western and the eastern edge of the mummy floor that was covered over with painted barrel vaults have two porthole Windows. Upstairs planned as square is made of Stone cutting.The exit door that can be reached by a staircase in two sides and four steps on eastern front is the most spectacular and the most ornate part of the kumbet.Entrance is enclosed within rounded rectangular frames in cord shape.Long sided pointed arched door niche with small columns was located to the two corners of the long and narrow door here.The charter of the waqf of the kumbet was placed on the entrance door and
muqarnases completed this.Above this the other epitaph of the kumbet was put. The body walls of the kumbet are decorated with rosettes and divided by pointed arches.The interior is exremely simple, rectangular mihrap niche was placed in the middle of qibla wall.The Windows on the west and North were opened inside Bursa arched niches.Kumbet was used as a masjid for a while.The General Directorate for Foundations has restored the kumbet between 1966-1967 years. The kumbet being talked about is known as Havai baba kumbet amongst people but in the cadastral record book No.413 and in the Bitlis Annaul dated 1316 he is referred as Seyh Necmettin Habi Baba.