Colorado & Southern No. 9 is a B-3A class 2-6-0 "Mogul" type narrow gauge steam locomotive built by the A.L. Cooke Locomotive Works of Patterson, NJ in 1884, originally for the Denver, South Park & Pacific Railroad (DSP&P) as their No. 72. The following year, in 1885, it was renumbered to 114. Four years later, in 1889, the DSP&P was sold to the Denver, Leadville & Gunnison Railway (DL&G), which later consolidated into the Colorado & Southern Railroad (C&S) in 1899. Following this, it was renumbered again to C&S 9. Within a few years, it was reboilered with a new wagon top boiler and later, in the late 1910s, it also received a new frame.
It was primarily used in passenger service and also pulled the last C&S passenger train from Leadville, CO to Denver, CO on April 10, 1937. After its retirement from the C&S, it was saved from the scrapyard to participate in the 1939-1940 New York World's Fair and later retired from service altogether in 1941. It would be selected to operate at the Chicago Railroad Fair from 1948 to 1949 and was later leased to the Black Hills Central Railroad in Hill City, SD until eventually being sold to the Colorado Historical Society in 1988. Eventually, the Uhrich Locomotive Works in Strasburg, CO restored the locomotive to operating condition in time for the 2006 operating season at the Georgetown Loop Railroad. Unfortunately, it proved to be too small for operating the tourist excursion trains between Georgetown and Silver Plume, CO. It last operated in September 2006, was officially retired from tourist excursion service in 2007, and later traded to the Rotary Snowplow Park in Breckenridge, CO in exchange for former International Railways of Central America 2-8-0 type locomotive No. 111.
As of today, it currently remains on static display at the Rotary Snowplow Park in Breckenridge, CO. Whether or not it will ever run again anytime soon is yet to be determined.