SECR Folkestone Class

The SER Folkestone Class was a series of early express passenger locomotives designed for the South Eastern Railway during the first decade of the railway's operation, associated with the pioneering period of the SER's expansion through Kent to reach the Channel port of Folkestone — the town from which the class took its name — and then Dover. The SER's route to Folkestone, opened in 1843 through the North Downs via the long Sevenoaks tunnel and then across the Weald, was one of the most challenging early railway routes in Britain for its engineering demands, and the motive power required for this demanding line helped shape the SER's early locomotive procurement.

James Cudworth, who became SER Locomotive Superintendent in 1845, inherited a varied and often difficult fleet of early locomotives built by various manufacturers to meet the SER's immediate operational needs. The Folkestone Class designation covers one of the early SER express types from this period, likely a Crampton-influenced or 2-2-2-type design suited to the express working between London Bridge and the Channel ports that was the SER's most prestigious and commercially important traffic from the railway's earliest years.

The early SER locomotive fleet of the 1840s–50s is not well documented in the same detail as the later Cudworth and Stirling designs, and the Folkestone Class represents an interesting but imperfectly recorded chapter of South Eastern Railway locomotive history. None was preserved.