Maunsell 'U' class 2-6-0 31790 of Guildford (70C) depot rolls into Redhill heading a Woking to Three Bridges engineer's ballast train in the early 1960s. 31790 was the first of a class of twenty locomotives introduced in 1928 as a rebuild from the troublesome 'K' ("River") class of 2-6-4 tanks originally introduced in 1917.