/vt/ - Virtual Youtubers

>>40274384
I doubt that would be a viable approach since the existence of subglacial lakes is caused by the high pressure exerted upon them by the ice sheets above. That eliminates the existence of any sizeable air pockets and also make the environment unsurvivable to most lifeform.

>>40274761
Lava caves are the one that comes to mind, although while they are sizeable, their width is somewhat limited (the widest one I can find is 22m), and they don't seem to be too long either. RL's largest cave systems are invariably limestone caves which do not bode well with active orogenic zones, and those can achieve pretty impressive interior size, to say nothing about how deep they can go. Any of these options could be partially flooded, although the result would be more like underground rivers than a singular sea since natural domes can only get so large before collapsing.