A British diver found what looks like a lake buried underneath the sea while swimming in a cave. He took some photos for us to contemplate it all.
Cenote Angelita (Angelita means little angel) is a deep water sinkhole and dive site. There is a cloud of hydrogen sulfide at around 30m formed by the decomposition of organic matter in the absence of oxygen. The cloud combined with the debris mound from the collapse of the sinkhole roof gives the surreal illusion of an underwater lake and island.