Crystal Mill, an 1892 wooden powerhouse located on an outcrop above the Crystal River in what remains of an old mining town, Crystal, high in the Rocky Mountains in Gunnison County, Colorado. Although called a mill, it is more correctly a compressor station, which used a water turbine to drive an air compressor to run power machinery at nearby silver mines. While the Crystal Mill is often reputed to be the most photographed site in the state, this is logistically impossible, as it is reached by only two precarious high-mountain dirt roads, including one from the town of Marble that is pocked with ruts, and large stones and advisable for four-wheel-drive travel only. Wheras more than 400 people once lived in Crystal during its heyday in the early 20th Century (when the town even had two flourishing newspapers), fewer than 10 people -- including the town "mayor" -- live there today (2015), and then only in the summertime when Crystal is not snowbound. Photo by Carol Highsmith