It is a rock that forms a natural arch above the sea. The place is near Corinth and it is a really beautiful spot in the nature.
In a blog post we found this:
The Seal Cave is one of the purest and untouched parts of Loutraki region as it has remained unknown for years, because of it’s difficulty to access. Access to the cave is by boat or through a rough, pine-covered path.
Actually it is not that difficult to reach. It is true that you need to walk a little bit up and down but it is fairly easy.
After following the path this is what you will find.
It is also possible to go down, the path is super slippery but they have added some ropes to help you go up and down safely. Nothing extremely hard, but a hand for you to get there safe!