|'Cenote Samulá' from Turismo|
Samulá cenote. Cenotes are (mostly) underground rivers. Though some of them are out in the open, many of them are only accessible through cave systems, formed by a badass meteor impact 65 million years ago. This is one of my favorite ones, about an hour and a half away from where I live, and like 20 minutes away from Chichen Itza. Those vine-looking things are actually the roots of a tree that's at ground level.