I’m on my way home now, and the last few days have been so hectic that I haven’t been able to post much (and I’ve only occasionally had internet access). We spent last Monday in Yellowstone National Park, and exited through the northeast gate, which took us along US 212 (Beartooth Highway). This is, in my opinion, one of the most beautiful drive in the country.
This highway winds up rapidly through the mountains, and culminates in Beartooth Pass; 10,947 feet according to Wikipedia (my iPhone GPS at least was within the margin of error):
Geologically these mountains are formed from a complicated series of mostly Archean metamorphic rocks (especially gneiss) that seem to change in character every few hundred yards. The area was heavily sculpted by alpine glaciers during the Pleistocene, and U-shaped valleys are everywhere: