The two original locomotives, No. 1 The Earl and No. 2 the Countess were built by Beyer Peacock & Co. Ltd. at their Gorton Foundry, Manchester in 1902 to a compact and sturdy design capable of handling the trains on this steeply graded railway. The pair coped with all the traffic on the line from its opening in 1903 to closure in 1956. Under the GWR and BR, they ran as Nos. 822 and 823. From time to time they went for overhaul at Oswestry Works and were sent there on closure, returning to Llanfair Caereinion in the 1960s to commence work for the Preservation Company. During the period 1997-2001 the locomotives were fully overhauled in the workshops at Llanfair. This included the fitting of new boilers and cylinders, intended to ensure that both were available for operation during their centenary year in 2002 and that of the railway in 2003. The locomotives were named in honour of the Earl and Countess of Powis as the Earl did much to support the construction of the railway at the turn of the last century. Currently The Countess is turned out in Great Western livery and represents the locomotive's appearance during the 1930s.