There's a massive cave system under Florida. This diver helped to map it out.
As four more holes opened up in Hudson, there are now 20 depressions in one community, some of them growing. The holes started opening last week - in a Pasco County neighborhood that happened to be built on top of caves.
They've been under the land for centuries, and in the 2000s, a group of intrepid divers went down to map them out. https://on.wtsp.com/2P9ibpK