The BR Standard Class 7, otherwise known as the Britannia Class, is a class of 4-6-2steam locomotive designed under Robert Riddles for use by British Railways for mixed traffic duties. Fifty-five were constructed between 1951 and 1954. The design employed results from the 1948 locomotive exchanges undertaken in advance of further locomotive classes being constructed. Three batches were constructed at Crewe Works, before the publication of the 1955 Modernisation Plan. They were numbered 70000–70054.