Swim through a Yucatan Peninsula Cenote - these were open caves with dripping water, stalactites, and stalagmites during the last ice age when sea levels were lower. Now the glaciers that covered Europe and North America have melted and sea level rose, flooding these caves.
A truly majestic nature video…take a trip diving underwater in the El Toh cave in the Yucatan. Note how there’s clear evidence of the time when water levels were lower - totally submerged stalactites and stalagmites. Plus the footage is amazing.