The LNWR Samson Class was a class of ninety 2-4-0 steam locomotives built by the London and North Western Railway at their Crewe Works between 1863 and 1879. They were officially designated Curved Link 6-ft Passenger due to the use of Stephenson valve gear which included a curved expansion link between the fore and back eccentric rods (earlier LNWR designs had used the Allan valve gear which had a straight expansion link) and the use of 6-foot (1.829 m) diameter wheel centres, which, together with 1+1⁄2-inch (38 mm) thick tyres gave a driving wheel diameter of 6 feet 3 inches (1.905 m).