The Diros Cave is an unusual one, in that it’s half-filled with water, so you go through most of it by boat.

What you do is that first you walk in through a corridor carved into the rock, by which you come to a platform facing the water.

You wear a life jacket that you’re given at that place (though there is practically zero probability for an accident), and get in a boat that carries 8-10 people.

That includes your guide, who will use a paddle to propel the boat, and at the same time explain the various features of the cave.

Now, if you understand English and not Greek, you’ll be lucky if your guide can speak in English, and you are among a group of English-understanding people in the boat, so you can ask your guide to use English.

Otherwise, forget about learning details such as how deep the water is (it’s more than the height of a person, at most places), how deep under the surface of the land the cave lies (it goes under a hillside, so that depth varies), or how long it is (the path that you will traverse by boat is around 100 m, but because you move slowly it appears longer; but there are other pathways in the cave that the boat cannot reach).

It’s a shame that the management of the Diros Caverns (a state-sponsored organization) does not make sure that guides are hired who know at least one foreign language, and that groups of visitors are arranged according to language understood.

Anyway, if you exclude the potential language barrier, the inside of the cave is spectacular. The water is crystal clear and brackish (don’t taste it, it’s not potable), and the cave ceiling is littered with stalactites (see pictures).

There must be stalagmites on the bottom, too, because the cave has not been always flooded with water, but you can’t see them except where there are bright lights placed underwater.