George Stephenson's first steam locomotive, built in 1814, was called Blücher.
Stephenson constructed Blücher for the Killingworth colliery railway in Northumberland, England. The locomotive was designed to haul coal wagons along rough wooden and iron-edged track. It used flanged wheels and improved methods for transferring steam power to the wheels, helping demonstrate that locomotives could work effectively in industrial service.
The name referred to Gebhard Leberecht von Blücher, the Prussian field marshal who fought Napoleon. Blücher was not a passenger locomotive and was built several years before Stephenson's better-known Locomotion No. 1, which hauled the opening train of the Stockton and Darlington Railway in 1825.
Stephenson continued refining locomotive design at Killingworth and later at other railway works. His developments contributed to the practical adoption of steam railways, but early engines varied considerably in their boilers, gearing, and methods of transmitting power. Blücher is therefore best understood as an important experimental and industrial predecessor, not as the first locomotive ever built.