File:Black Hills Central No. 110 on the Black Hills Central Railroad in Keystone, South Dakota - 09.jpg

English: Back Hills Central #110 is a 2-6-6-2 tank engine steam locomotive built by The Baldwin Locomotive Works in 1928 for the Weyerhaeuser Timber Company of Vail, WA. Its next owner was The Rayonier Lumber Company where it received a tender from Rayonier #101 and was retired in 1968. This engine was later displayed at the Wasatch Mountain Railway in Heber City, Utah, and then sold to the Nevada State Railway Museum. The 110 was sold to The Black Hills Central Railroad in 1999, and was trucked from Nevada to South Dakota on four semi-trailers. Restoration on this engine by the mechanical crew of the BHC was completed in the spring of 2001. It is the only 2-6-6-2T Mallet in service in the world.