Locomotive built in 1881 still pulling passenger trains. 

Denver and Rio Grande Western #346 is one of the oldest operating steam locomotives in the United States. The narrow gauge locomotive built by Baldwin in 1881, still pulls occasional passenger trains at the Colorado railroad museum in Golden, Colorado. The large device at the top of the smoke stack is called a ridgway spark arrestor also know as a "bear trap". It was designed to capture hot coal cinders where they went down a chute and later emptied. The locomotive looks very much like it did over 137 years ago.