Stockton & Darlington Railway, in England, first railway in the world to operate freight and passenger service with steam traction. In 1821 George Stephenson, who had built several steam engines to work in the Killingworth colliery, heard of Edward Pease’s intention of building an 8-mile (12.9-kilometre) line from Stockton on the coast to Darlington to exploit a rich vein of coal. Pease intended to use horse traction; Stephenson told Pease that a steam engine could pull 50 times the load that horses could draw on iron rails. Impressed, Pease agreed to let Stephenson equip his line.
On Sept. 27, 1825, the first engine ran from Darlington to Stockton, preceded by a man on horse carrying a flag reading Periculum privatum utilitas publica (“The private danger is the public good”). When the horseman was out of the way, Stephenson opened the throttle and pulled his train of wagons carrying 450 persons at a speed of 15 miles (24 km) per hour.