It is located in the Merdivenlikuyu Site of Ayaş Town, 20 km to Erdemli District, Mersin. The place was given the name “Merdivenlikuyu” (literally: the well with stairs) because of the stairs that lead down the huge cistern dug on the rock, which is one of the most attractive structures of the antique city. Its name in antiquity, Elaiussa, means “olive grower”, and “Ayaş” is said to be a derivation of this phrase. According to another theory, this place was given the name because some of the Turkmen tribes that had settled in Ayaş District of Ankara also came here to found this settlement. The coins found in the area revealed that Elaiussa was a sacred and autonomous city as of the second half of the 1st century BC. Elaiussa, which was initially founded in the 2nd and 1st centuries, enjoyed its prime during the Empire and Early Christianity periods. Remains found in the site include the theatre, agora, a large public bath, Byzantine palace, temple and the necropolis area. Some of the small findings gathered in the excavations conducted in Elaiussa Sebaste are exhibited in Mersin Museum.