I've been looking into locomotives.
Big Boy: The world's largest steam locomotive, twenty-five Big Boys were built exclusively for Union Pacific, the first of which was delivered in 1941. The locomotives were 132 feet long and weighed 1.2 million pounds. Because of their great length, the frames of the Big Boys were "hinged," or articulated, to allow them to negotiate curves. They had a 4-8-8-4 wheel arrangement, which meant they had four wheels on the leading set of "pilot" wheels which guided the engine, eight drivers, another set of eight drivers, and four wheels following which supported the rear of the locomotive. The massive engines normally operated between Ogden, Utah, and Cheyenne, Wyoming.
Although there are no Big Boys left in operation today, eight of them eventually were donated for public display in various cities around the country. They can be found in Pomona, California; St. Louis, Missouri; Dallas, Texas; Omaha, Nebraska; Denver, Colorado; Scranton, Pennsylvania; Green Bay, Wisconsin; and Cheyenne, Wyoming.