Want even more risks, GRINS, I scuba dive flooded Caves in Cenotes in Playa Del Carmen is a dream like experience...................all the features were formed during the last ice age as dry caves when the Sea Level was 200 foot lower than it is today, so now you "fly/swim/glide" through the VERY fragile overhead environment. Here's a Cave Dive Video I shot deep in the Mayan jungle.
https://vimeo.com/114802443