The GNR Stirling Single is a class of steam locomotive designed for express passenger work. Designed by Patrick Stirling, they are characterised by a single pair of large (8' 1") driving wheels. Originally the locomotive was designed to haul up to 26 passenger carriages at an average speed of 47 miles per hour, they could reach speeds of up to 85 mph.

A total of 53 were built at Doncaster, in three series introduced in 1870, 1884, and 1894. The GNR did not number its locomotives sequentially, instead using numbers freed up by withdrawing older locomotives. Thus the 1870 series was numbered between GNR No. 1 and 671, the 1884 series 771-8 and 1001-2, and 1894 series 1003-8.

With the arrival of the Ivatt Atlantics after 1898, the class began to be displaced from the most prestigious express services. Several examples were rebuilt by Henry Ivatt after 1898 with a domed boiler, but withdrawals of the 1870 series began in 1899. The last examples of the class were in use on secondary services until 1916. The first of the class, No 1 is the only engine to be preserved. It is exhibited at the National Railway Museum, York. It was restored to running order during the 1930s for the fiftieth anniversary of the Race to the North and steamed again during the 1980s.