SR River Class

The SR River Class was the name applied to the SECR K Class 2-6-4T locomotives after Maunsell rebuilt them as 2-6-0 tender engines on the Southern Railway — see the main SECR K Class entry for the full story of these locomotives. The River Class name came from the individual locomotive names applied to the rebuilt engines, which were named after English rivers: River Frome, River Tamar, River Avon, River Stour, River Medway, and others. The renaming as 2-6-0 tender locomotives after the derailment investigations that revealed the 2-6-4T's instability at speed gave rise to the SR U Class designation, with the River names carried forward.

See the SECR K Class entry for the full history of the original 2-6-4T design and its rebuilding as tender 2-6-0s. The SR U Class River 2-6-0s gave long and reliable service on SR secondary express and mixed-traffic duties, and several are preserved on heritage railways.