In 1823 George Stephenson along with four other people - his son Robert, the Quaker businessman Edward Pease, Pease's cousin Thomas Richardson and Michael Longridge who managed Bedlington Iron Works - opened the world's first purpose built locomotive factory at South Street on Forth Banks, Newcastle upon Tyne. Robert, then aged 19, was the Managing Partner. It was at these works that 'Locomotion' was built in 1825 for the Stockton and Darlington Railway. In 1829 Rocket' was built there for the Rainhill Trials. Between 1828 and 1830 Robert developed an economically viable prototype in 'Northumbrian' and 'Planet' which remained the basis for all future steam locomotive development.

Locomotives built at these works were exported to developing railways all over the world and were often the first locomotives to be seen and used in those countries. Stationary engines for collieries, marine engines, bridges and even a steam driven chain ferry were all constructed here. At Robert's death in 1859 the firm was the largest employer on Tyneside. By the early 1890s the works had expanded to occupy all available land on Forth Banks and it became necessary to seek a fresh site. Suitable land for a new and enlarged works was found at Springfield, on the north-east side of Darlington, which opened in 1902. The old works in Newcastle finally closed in 1904.

While some of the locomotive shops were acquired by their Forth Banks neighbours, R. & W. Hawthorn Leslie, the bulk of the site passed to George and Jobling, motor engineers. They were engaged in importing Ford chassis and building bespoke bodies for them. George (of George and Jobling) was one of the first 100 pioneer aviators and during the First World War aeroplanes were constructed on site.