Isa Bey Mosque is located on Ayasuluk Hill. on the western slopes of St John’s Basilica.

The mosque built by Isa Bey In 1375. is a building from the Seljuk Period. The building is the oldest known example of a typical Turkish mosque with its courtyard and Anatolian columns. With its decorative techniques and its main gate’s monumental height it bears the features of traditional Seljuk architecture.