You both are right. It's the Wild Goose railroad, outside Nome. Originally it ran about 6.5 miles north to a gold mining district, jogging around the west side of Anvil mountain.
In later years it extended many miles north over the tundra, and was renamed the Nome Arctic. This railroad was the westernmost and northernmost railroad in the Americas.
The track I showed is about 30 yards long, fully intact, and cleanly cut at each end. This segment is literately at the westernmost point. Rumors are that there is another segment, with a handcar or cart, at the northern end.
The Army commandeered the railroad during WW2, to defend against a Japanese invasion. Later, an entreprenuer offered a rail excursion for a year. It was scrapped around 1954, leaving just those two segments of track.