İsabey Mosque is one of the oldest and most impressive works of architectural art remaining from the Anatolian beyliks. The mosque is situated between the Saint Jean Church and the remains of the Temple of Artemis on the skirts of the Ayasulig Hills at Selçuk, Izmir, in Turkey. It was built by the architect Şamlı Dımışklıoğlu Ali in honor of the Aydın Bey, İsa. It has been used as a caravanserai in 19th century.
The mosque has two main entrances, to the east and to the west. The western wall has inscriptions and geometric shapes engraved. These walls are covered with marble, whereas the façades on the remaining sides are made of cut stone. It is built asymmetrically on a 48 m (157 ft) by 56 m (184 ft) base. The rims of its domes (of diameters of 9.4 m and 8.1 m) are decorated with İznik (Nicaea) tiles. 12 round columns stand inside its courtyard encircled with porches. Its brickminaret is built on an octagonal base, and the upper part from the balcony is ruined. The mosque had another minaret on the west, which is totally destroyed now. The mihrab (niche or altar) was moved to another mosque, due to a door opened there. There is an octagonal Seljuk türbe made of stone and bricks, with a pyramid shaped roof, right next to the mosque.
This mosque, located on the slope containing Ayasoluk Castle and the Church of St. John, attracts the visitors to the latter structure with its beauty.
The Mosque was built by the architect Aliye son of Ãamlý in 1375 on orders by Ãsa Bey, son of Mehmet, leader of the Aydýnoðullarý.
This is one of the first examples of a mosque containing two congregation places, and as such it represents an important example of the transition from Seljuk to Ottoman art.