Çakırhüyük (formerly known as Kaysun or Armenian: K'esun)[1][2] is a town (belde) and municipality in the Besni District, Adıyaman Province, Turkey.

[7] The region was conquered by the Byzantines in the late tenth century and then fell to Armenians after the Seljuk invasions.

The principality of Kogh Vasil was centered on Kaysun who restored its fortification and build a palace in the town in the late 11th century.

[19] In 1131, the Danishmend Emir Gazi besieged the place in which Joscelin I, Count of Edessa, had installed the Jacobite Patriarch of Antioch.

A certain bishop called Iliyya wrote a short historic treatise, which was later used by Michael the Syrian in writing his chronicle.