Amtrak’s California Zephyr begins the massive climb up the Front Range of the Rocky Mountains.
The second to bottom picture shows the train tackling the famous “Big Ten Curve” which helps the train ascend over 500+ feet in elevation.
Take note of the derailed and abandoned hopper cars.
Those freight cars have been sitting there for well over 30 years now. The tracks surrounding them have since been ripped up (due to a single-track project that tore out the second track), but the tracks just under their wheels still remain.
Go figure :P
The bottom picture shows a more broad shot of a different California Zephyr going downgrade through the bottom of Big Ten, this time with a more visible appearance of the curve itself.