If the name "Devil's Den" doesn't deter you.
There are a lot of amazing places to snorkel around the world — remember Iceland's Silfra Fissure? For stateside snorkelers and divers, you don't have to travel that far to get a completely one-of-a-kind water experience. In fact, you can explore a prehistoric cave in Williston, Florida.
Devil's Den has been around since at least the Pleistocene Age, judging by the ancient fossils that have been discovered in the area. It's actually a dry cave that's also home to an underground spring — the cave opening is located 60-feet above the surface of the water.
So where did it get a name like Devil's Den? The water maintains a cool 72-degree temperature, meaning blasts of steam can be seen spouting from the opening on especially cold winter nights (if you can call a Florida winter "especially cold").
People travel from around the world to snorkel and dive at the spring — no general swimmers allowed, but there are other swimming holes out there for those just looking for a refreshing dip. YouTube user Ana Wildgust recently uploaded a photo giving the curious a peak into this diving destination.
Check it out:
Erika Owen is the Audience Engagement Editor at Travel + Leisure. Follow her on Twitter and Instagram at @erikaraeowen.