steam locomotive hercules at hythe station kent Hercules is a steam locomotive that operates on the Romney, Hythe, and Dymchurch Railway (RH&DR) in England. The Romney, Hythe, and Dymchurch Railway is a narrow-gauge railway that runs along the coast of Kent, from Hythe to Dungeness. Hercules is a class of locomotive on the RH&DR, and it is one of the three oldest locomotives still in operation on the line. The locomotive was built in 1925 by Greenly's Model Engineers Ltd. It is a 4-8-2 "Mountain" type steam locomotive, which means it has four leading wheels, eight driving wheels, and two trailing wheels. The name "Mountain" comes from the locomotive's ability to handle mountainous terrain.