4 was out of service needing a major overhaul, and as a result never worked under British Railways following nationalisation in 1948, as the Corris closed on 20 August that year.

[3] The Talyllyn Railway was built in 1865 and ran from Towyn (now called Tywyn) to the slate quarries of Bryn Eglwys, only a few miles from Corris.

The line and quarries were bought by Sir Henry Haydn Jones, the local member of parliament, in 1911.

The venture made little money, but despite the closure of the quarries in 1946, Haydn Jones continued to operate the railway at a loss until his death in 1950.

[4] That same year, a group of enthusiasts, including the author Tom Rolt, had looked at the possibility of operating the railway on a volunteer basis.

With the agreement of Haydn Jones' widow a deal was made, and control of the railway passed to the newly formed preservation society.

In 1958, Dr Giesl-Gieslingen approached British Railways to offer a free trial of his Giesl ejector.

On 17 May 2005 a new-build Tattoo class locomotive, similar in design to No.4, arrived on the Corris Railway where it became No.7, and currently hauls passenger trains there.