The Cehennemağzı Caves are on the northern edge of Karadeniz Ereğli's historic centre, about 45 minutes east of Akçakoca along the coast road. In antiquity Ereğli was known as Herakleia Pontike, and the valley where the caves are was called the Acheron Valley.
According to Greek mythology, Heracles descended to the underworld here to capture Cerberus, the three-headed dog of Hades. The caves take their name from this legend; in antiquity the place was also known as an important oracle.
The three caves are actually ancient quarries cut side by side. The first has a mosaic floor, columns and niches for oil lamps; it is thought to have been used as a secret place of worship and church in the early years of Christianity. The second extends into the mountain, and the floor of the third is covered by groundwater. The caves belong to the Ereğli Museum and opened to visitors in 2001.
Before you go
- Sources give different visiting days and hours; call the Ereğli Museum (+90 372 323 45 57) before you go.
- It's cool and damp inside and the floor can be wet; wear non-slip shoes.
- Plan it for the same day as the Ereğli Museum and the Gazi Alemdar Museum Ship on the seafront.




