It is claimed Anatolia's first mosque was built on this spot, on top of a former Roman temple, however, it has been rebuilt and renovated many times.

From a Turkish site I quote (through Google translate): "It is thought that it was converted from a Roman temple to a church, and then converted into a mosque after the conquest of Antioch. After the conquest of Antakya in 638, it was assumed that the first construction of the mosque was carried out by Abu Ubeyde Bin Cerrah and the second construction by the Mamluk Sultan Baybars in 1222. The courtyard of the mosque is paved with smooth cut stone. There are madrasah rooms in the north and west of the courtyard, and a fountain with 12 columns and inscriptions in the northwest corner. Hz. It bears the name of an Antioch[ian citizen] who first believed in Jesus' disciples and gave his life for this cause. It is known for its high body with a large body [probably: dome] and a wooden minaret [I think: a wooden balcony, the minaret being in stone) on the hill [a raised structure]. There are tombs of two saints in two rooms on the left and right sides of the minaret. There are the chests [graves] of the two apostles John (John) and Yunus (Pavlos) sent by Jesus. The gate to the southeast of the courtyard opens for a visit to Habibü'n-Neccar. There is a large room on the right to a smaller room, and then there are stairs, where the tomb of Habib Neccar and Şem, which is 4 m below the mosque floor, goes down."

In 2019 I took pictures of the graves.