sombrero's good just shallow and the sea floor is more grassy so not too hot to go to, your more lookin for deep pits to dive in and steppin back on shallow after you hit your head lol, but you can still havfe some fun at high tide, id recommend it for sure, but you can go to captain hooks marina or other places in marathon and for 23$ they take you on a 4 hour snorkel trip to see starfish and lighthouses and other cool stuff, really ya cant beat it for the price, but all the keys are sandbars so you pretty much have to go out couple miles beforeyou can do some real scuba or snorkelin, if your just walkin in from the shore its just to play around,