Located at the foot of the Böyrek Mountains, 500 meters from Haydar Sultan Village, there is a well in the garden of the mausoleum, called "Deliler Well", which boils constantly despite its cold water.
It is rumored that Haydar Sultan, son of Hoca Ahmet Yesevi, who played an important role in the Turkification of Anatolia, was captured by the enemy and imprisoned in a well here. The Haydar Sultan Complex, built on a monastery that existed in the Late Roman or Early Byzantine periods, consists of a mosque, tomb, graveyard, fountain and well. The complex, which lost its original identity with the repairs made, has survived to the present day with a well called "Crazy Well" and two inscriptions. Deliler Kuyusu is in the courtyard surrounded by a wall next to the mosque. There is a 50 cm diameter well collar, and below it there is a 60x60 cm square well. The mouth of the well is raised with concrete linings and its depth from the ground is about 2 meters.

The tomb is in a very important position by many people with religious sensitivities. It is a frequent destination for many visitors in every period of the year and especially in August when the Hacı Bektaş-ı Veli Commemoration Ceremonies are held.

Sources:

https://www.kirikkale.com.tr/mekan/haydar-sultan-turbesi