The holes were created/needed for the scuttling, how they get used after that...
There are obvious similarities since they are both 'overhead' environments. I run line similar to a cave dive.
Some of the bigger differences are:
Caves often have one exit, Wrecks usually have multiple exits
Wrecks generally have more entanglement hazards and it is harder to get EMS services if things go bad.
Very cool!
