The Corycian Cave on Mount Parnassus, near Delphi, Greece is a very old and sacred cave closely connected to the myths and rituals of ancient Greece. The Corycian caves were named after one of the nymphs that the ancient Greeks believed inhabited the site. It was considered sacred to the nymphs, the Muses, and to Pan himself. Archeologist have found evidence of its use back to Neolithic times and it has been used as refuge from by the local population through the ages. One is able to visit and there is quite a large expanse inside lit simply by a narrow opening to daylight. There is much more to the cave further back, but it gets dangerous without the proper gear.
The walk is a lovely hike from Delphi in good weather but beware the heat in summer months. The first part of the walk is fairly straight forward but it gets complicated further up. I don’t have a single source that I used for my route to the cave. I pieced together multiple articles and still had to do some figuring myself. I’d spend some time looking up your route and maybe buying a map too. Of note is that you will likely pass a small home/farm, near a water source and side road, that has two aggressive and unrestrained dogs. I would be sure you know how to handle this situation before you hike from Delphi to the caves. I wasn’t bitten, but their behavior tells me that either have, or may likely, bite someone. Again, they are completely unrestrained and wandering the hillside near the home. Be careful.