Building a snow shelter is an essential snow country skill, although an igloo is a quite skilled task.
The first one takes about 20 hours, and looks quite comical. Each following one takes many hours fewer.
I love the film, and the statement that it took them 1-1/2 hours! I've never done that! Next time, I'll use a machete.
The trick is to not get soaked doing it, which is not easy.
The unskilled version is the Quinzy ( quinzhee )
