Big Ten Curve, Colorado
Rising out of the plains at the front range north of Denver, the railroad makes a long slow curve of 270 degrees. Called the Big Ten, because the radius of the track’s curve is ten degrees, based on the method railways uses to measure curves. Built in the early 1900s, this section of track was once the Denver and Rio Grande Western RR, and is now Union Pacific. It is also the route of Amtrak’s California Zephyr, passenger service from Chicago to Emeryville, California. In the middle of the curve is a row of about two dozen hopper rail cars filled with cement. In the early 1970s they were permanently parked on a separate track inside the curve, and welded to the track, to serve as a windblock in this notoriously windy and snowy stretch of track.