The old miners' union hall in a former elegant residence in Telluride, once a mining boomtown and now a popular skiing destination in Colorado. More than 350 miles of mining tunnels (the approximate distance from Los Angeles to San Francisco) run from Telluride under the Rocky Mountains to Silverton -- another old Colorado mining boomtown that would have been almost inaccessible by roads in those days. Photo by Carol Highsmith, 2016.