Caption: "Unexpectedly heavy snows forced Central Pacific's pioneer builders to build snow sheds over the railroad in the High Sierra where 30-foot packs handicapped construction forces. This photo was taken in 1867. Eventually, about 40 miles of sheds covered an almost continuous stretch at high elevations. Today only about three miles remain due to powerful new snow plows and other improved machinery and methods for snow fighting. Southern Pacific Photo X 157"