minutes on each circuit. The Promontory Junction Station was abandoned in the early 1990s. Beginning in 2010, both trains have operated simultaneously on busy weekends allowing more frequent departures from the two stations. Omaha Zoo Railroad Trains Visitors to the Henry Doorly Zoo ride behind one of three locomotives for the trip around the park. Two of the engines are steam locomotives, and though they are similar in the basic principle of their operation, the two locomotives are otherwise quite different and guests can easily distinguish between them. The third engine is a diesel, which operates very differently from the steam locomotives. New coaches have been added and replacing the old coaches. 119 is the less powerful of the zoo's two locomotives and regularly hauls a train of five open-air coaches. This engine is known for its colorful paint scheme, polished brass, and sweet-sounding Nathan six chime whistle. No. 119 was the original locomotive on the Omaha Zoo Railroad and was custom built for the zoo in 1968. It was built by Crown Metal Products of Wyano, Pennsylvania, a company that built replica steam trains for amusement parks and zoos all over the country. In honor of zoo railroad benefactor Union Pacific, the engine was decorated to resemble the Union Pacific's ceremonial engine used at the 1869 completion of the first transcontinental railroad. It is a 4-4-0 "American" type locomotive, meaning that it has four pilot wheels to help guide it through curves, 4 large driving wheels, and no trailing wheels. This type of locomotive was prevalent on American railroads from 1850 to about 1880, thus earning it the nickname "American standard". During the 119's first years at the zoo, it was underpowered and had difficulty pulling the train up the steep hills. Subsequent modifications by the Union Pacific and the zoo railroad's own shop have improved it greatly, and after a major rebuild in 1996–1999, it was deemed to be in better-than-new condition. During the rebuild, the engine also received a cosmetic makeover. Originally painted black, gold and red, it emerged resplendent in a beautiful and more historically accurate scheme of crimson, maroon, and olive green. A new stained wood cab replicating the one on the original UP locomotive was also fitted. This engine returned to service in May 2013 after an overhaul. Riva, number 104, is the zoo's second steam locomotive, acquired in 1974. It is a 0-6-2