Excalibur is a coal fired 2-4-2 tank engine. Works No. 293 it was built in 1993 by Exmoor Steam Railway and was originally called River Churnet and painted dark green. It is one six locomotives of this type to have been built at Exmoor which gradually all have got a little larger.

The engine was originally built to12.25 inch gauge as one of a pair of engines. It ran at Exmoor on the railway there until purchased for Rudyard Lake railway by Peter Hanton, named River Churnet and was re-gauged to 10.25 inch gauge. Since arriving at Rudyard it has been a reliable and popular engine. It was given the name Excalibur in 2003 and repainted in black as part of a theme around the legends of King Arthur.

Excalibur has been in use every year since its arrival in 1993. It was rebuilt in 2003 with a new boiler and taller cab after travelling an estimated 20,000 miles in 10 years. It has an open back cab and is popular in hot weather. The engine was the first to be fitted with twin pipe air brakes in 2003 as part of a programme to equip the whole railway. It has needed very little other repair work. Excalibur has cylinders 4 inch bore X 5inch stroke. The boiler pressure is 150 Pounds per square inch and it has 11 inch diameter driving wheels. The valve gear has roller bearings throughout as do the axle boxes. It has the shorter wheelbase like the earlier 3 engines built of this type.

The main improvement to the engine after rebuilding was the fitting of sanders in 2008/9. This greatly improved adhesion in wet weather or in the autumn leaf fall season. The engine was dismantled for overhaul during November 2012. It had repairs to its wheels, smoke box, new boiler tubes and other work.