There are two big natural caves mentioned as Heaven and Hell in 5 km west of Corycus. Heaven Graben was formed by collapse of ceiling as a result of erosion caused by an underground stream. In the southern end of the Graben which is 200 meters wide and 70 meters deep, entrance of the cave and a church are notable. Temple built in the 3rd or 2nd century B.C. was converted into a church in the 5th century A.D. . In the inscription over the gate, it is written that the church was dedicated to the Virgin Mary by a religious person named Paulus in the 5th century A.D.
CENNET ( HEAVEN ) SINKHOLE
Elliptic Cennet sinkhole, one of the two natural wonders formed naturally, has an opening measuring 250 x 110 meters (820 x 360 ft). At the bottom of the formation towards south, which is 70 meters in depth, there is a large cave entrance which is 200 meters long with a 135-meter deepest point. At the entrance of the cave there is a small rectangular monastery constructed from cut stones. The access to the church is by stairs. It is possible to reach the bottom of Cennet by a staircase composed of 450 steps.
CEHENNEM ( HELL ) SINKHOLE
Cehennem Sinkhole is 75 meters north of Cennet Sinkhole. Its top opening is 75x 50 meters (210 x 150 ft). As the upper edge of the opening is concave there is no access to the bottom of Cehennem. It is 128 meters deep. According to Greek mythology, after a fight Zeus kept Typhon, a monster with over a hundred serpent heads, temporarily in Cehennem before imprisoning him under Mount Etna.
VIRGIN MARY MONASTERY
Virgin Mary Monastery is located at the entrance of the cave in Cennet Sinkhole. It was constructed from cut stones, rectangular shaped and has east – west exposure. There are six arched window openings on the North and South Long sides of the building. The four-line inscription on the entrance gate at the western part of the church indicates that the church was built by a pious person named Paulus in memory of Virgin Mary. The apse in the eastern part of the church and the monk chambers on either side of this apse are covered with domes. The dome and inner wall parts of the apse are decorated with frescoes. Jesus Christ and his disciples are depicted in these frescoes. The monastery dates back to the 5th century.
TEMPLE OF ZEUS
Temple of Zeus is located on the south side of Cennet Sinkhole. The first phase of the temple is dated to the Hellenistic period. In the north wall of the temple, which was built in Doric order, on the stones that were not in the form of insitu (in its original place) the names of 130 religious men who served in the Hellenistic and Roman periods were inscribed. The temple was converted into a church during the Christianity period. The wall of the southern part of the temple is not present.
You can also see magnificent reliefs in the valley of Devil’s River (Şeytan Deresi) known as Adamkayalar near the Maiden’s Tower. Eleven male, four female, two children and a mountain goat reliefs inside the nine niches carved in rock in the steep slopes of the valley are dated to 2nd century A.D.