For several years, photographer Eric Guth has shot some amazing pictures of caves and hollows that form under glaciers. He explained how he knows where to look for good shots:
“I’ve found that melt water has everything to do with how glaciers change, move and create points of entry. As I’ve learned more about how water erodes, shapes and works the ice (as it does everything else on the planet, given enough time), I’ve learned where to look to find caves.
“More than where to look, where to listen. Where water enters from a nearby stream or exits from a sub-glacial river there is a good chance the erosive force of that water has created an opening. Whether that opening is safe or dry enough to explore is another question!”
You can view sixteen more photos at the link.