I'm constantly amazed by how little we know about the world we live in. You'd think something five miles long and bigger than a 40 story building, somebody'd notice it.
Nobody did until 1991, though, and then they didn't go explore it, that had to wait till four years ago, and look what they found! Now they're opening this baby up for tours, Woot! Sort of adventursome--it starts off rappelling 80 meters down into the entrance, but it's the WORLD'S BIGGEST CAVE!
Corporations think they know all about how to frack things up safely, even miles under the sea floor, but they never even knew this was even there. Hmmph. We keep finding things they didn't know.
It has it's own jungle! It has its own waterfalls! It has a river! New, undiscovered species! Stactities! Stalagmites! (points if you know the difference) It has Cave Pearls! It's the WORLD'S BIGGEST CAVE, and NOBODY EVER NOTICED IT!