While Pattie waited outside for disaster to strike (which never did), I followed the river into the tunnel. The river flowed from the heart of the glacier and the tunnel went back several hundred feet. This glacier is receding and it was only 50 degrees outside so there was a lot of melting with water dripping constantly.
The ice is very thick and solid therefore I never felt worried about it collapsing although I could sense Pattie thinking about it while I was exploring.
The second tunnel wasn't as large and only had a small stream flowing in it. This opening did not narrow as quickly as the river tunnel so it appeared that I could have gotten a lot deeper but this time I listened to Pattie's tingling spider senses...