The Cosquer Cave located in France,,,,,,,,,,

[Justdroppedin]

is situated about 37 meters (121 feet) below sea level and its entrance lies about 37 meters (121 feet) underwater. It contains around
600 paintings and engravings from the Upper Paleolithic period









https://i.redd.it/uze2au7n26ra1.jpg

[swan]

ok, the picture is all i need , I don't need to go there

[Gates07]

for a person to find something like that is quite remarkable, to swim in a tunnel that far down wow, if it is to be preserved then someone needs to somehow figure a way to block off the entrance, there appears to be adequate oxygen that guy did not have breathing apparatus on