Smallest armoured train

During World War II the 381 mm (15 in) gauge Romney, Hythe & Dymchurch Railway, which runs between Hythe and Dungeness along the coast of Kent, UK, was requisitioned by the British government. One steam locomotive, Hercules, and several carriages were given steel armour and machine guns were mounted on the train, both as a defence against invasion and to protect trains transporting war goods. With a track gauge roughly one quarter the width of standard gauge, the locomotives and carriages are correspondingly diminutive.