An 'Austerity', built by Hunslet, No. 3890 is the last steam locomotive built in this country for the home market. It was the 484th Austerity to be constructed. The locomotive became No. 66 in the South Yorkshire NCB fleet and was sent to Cadeby Main Colliery, Conisborough on 27 March 1964.

The locomotive was originally fitted with a mechanical stoker to assist in one-man operation, and a gas producer to reduce smoke emission - both a brave attempt to extend the life of the steam locomotive. The gas producer system and mechanical stoker fell into disuse, and conventional methods of firing were adopted, an ordinary grate being fitted. This meant that when the Conisborough area was designated a smokeless zone in 1970, the locomotive had to be replaced by an ex-BR diesel shunter.

After mainy years awaiting a heavy overhaul, including major tyre renewal works, No. 66 has now entered the restoration queue. The boiler has been sent away for overhaul, as has the chassis, both to South Coast Steam.  The chassis is expected back at Quainton before Easter 2008, when preparations for the return of the boiler will be started.