The 1815 Philadelphia train accident occurred on 31 July 1815, in Philadelphia, County Durham, England, when an early experimental railway locomotive, Brunton's Mechanical Traveller, suffered a boiler explosion. This engine, also known as the Steam Horse, ran on four wheels but was pushed by mechanical feet. This was both the first recorded boiler explosion and the first railway accident causing major loss of life, as 16 people were killed [some sources state 13].