This gallery contains photographs of the Union Pacific Challenger steam locomotive as it passed through Arkansas on 1-23-04 and 1-24-04. Union Pacific's No. 3985, an articulated locomotive with a "hinged" frame to allow it to negotiate curves, is 122 feet long. It weighs more than one million pounds, has six-foot diameter drive wheels and can reach a top speed of 70 miles per hour. No. 3985 was built in 1943 for fast freight service and was retired in 1959. In 1981, it was restored to running condition by UP employee volunteers for special service. The Challenger is based in Cheyenne, Wyoming.