From railrover

Steam locomotives are featured in Hellfire! these are found on the Vale of Rheidol Railway line which runs between Aberystwyth and Devil's Bridge. These steam locomotives are a 2-6-2T narrow gauge design and have been given the British Rail TOPS Classification of a Class 98.

There are only three of these Class 98 locomotives, all of which are based on this line.

To get to these you need to use either a DMU operated service train or travel on a Rail Tour to Aberystwyth which shares it's station facilities with the Vale of Rheidol Railway.

There is also a service hauled by STEAM which operates two round trips a day between York & Scarborough on Tuesdays & Wednesdays.