Is there really a submerged crater near Ile Ronde?

Yes there is one. I would love to go and see that crater. If I do, I'll try to take some pictures with an underwater camera and upload it for other people to see.

Apparently there is one and that's why it's a popular destination with scuba divers. However there's not much information on the net on this topic and I couldn't find any pictures of the submerged crater. Even pictures of Ile Ronde are hard to find. Let's hope that scuba divers going to see the crater upload some photos of it soon.