Crevasses often have vertical or near-vertical walls, which can then melt and create seracs, arches, and other ice formations. These walls sometimes expose layers that represent the glacier's stratigraphy. Crevasse size often depends upon the amount of liquid water present in the glacier. A crevasse may be as deep as 45 metres, as wide as 20 metres, and up to several hundred metres long.
When in outdoor public spaces where you are legally present, you have the right to capture any image that is in plain view (see note below about sound recording). That includes pictures and videos of federal buildings, transportation facilities (including airports), and police officers.
Conversations with police in the course of their duties are not private conversations, but many other things you may record on a public street are. 1  You have the right to videotape and audiotape police officers performing official duties in public. 2  You can record people protesting or giving speeches in public.