Bigger than Luray

The closest thing to this cave that I have seen before is the Luray Caverns in Virginia. Those are tiny compared to this cave. Unlike Luray these caves are not formed by limestone, but from underground rivers wearing away weaker stone. Guinness judges this to be the worlds largest underground lake because it is at least 4.5 acres big and 140 feet below the surface. Only 13 acres have been mapped. The cave extends even deeper-500 feet below the surface at its lowest point. .