I was fascinated by the glaciers, which are basically just rivers of ice. They're moving all the time, and the ones that go sharply downhill have more turbulence--crevasses and jags--than the ones that meander peacefully across the landscape.
Junea was interesting, too. It's the largest city in the United States, in terms of land area (a whopping 3,108 square miles, when all of NYC has only 321) and yet has less than 32,000 people (compared to NYC's 8 million). Loads of uninhabitable mountains and glaciers are within the city limits. Ravens and bald eagles fly all over the place there (and apparently squabble, though I didn't see that), and all the city trash cans are bear-proof. Because it's built right into the side of the mountain, these long staircases link one street to another higher up. Most bizarrely, even though it's the capital of Alaska, it can't be reached by road! You can only get there by boat or plane.
