The Great Western Railway (GWR) 4700 Class was a class of nine 2-8-0 steam locomotives, designed by George Jackson Churchward. They were introduced in 1919 for heavy mixed-traffic work. Although primarily designed for fast freight, the class also sometimes hauled passenger trains, notably heavy holiday expresses in the summer months. They were called "Night Owls" because they were primarily designed to haul goods during the night and that they could be seen simmering in the daylight, awaiting their nocturnal duties.