DIDCOT Railway Centre has unveiled major expansion plans after securing its long-term future.

Last month, Network Rail agreed to give the Great Western Society, which runs the centre, a 35-year lease for its home next to Didcot Parkway station, where the steam train collection has been since 1967.

Until then, the centre, which attracted 50,000 visitors last year, had a rolling six-month lease, making it difficult to attract funding for development.

The deal means the centre can press ahead with expansion plans and display more meticulously restored steam engines.

By the end of next year, at least three new steam engines will be on show, and a new museum and archive centre will open on the unused central sidings.

The first development this summer will be a new 180ft-long shed to house the only existing Steam Railmotor, rebuilt by the society with the help of a £768,500 lottery grant.

The vehicle dates from before the First World War, when the Great Western Railway experimented with steam engines inside passenger coaches.

The company ripped the power units from the carriages in the 1930s, so the restored Steam Railmotor 93 will be unique.

Another locomotive, 6023 King Edward II, will also go on show this summer after 25 years of restoration. The engine was rescued from a South Wales scrapheap in the 1980s, and the restoration project is finally nearing completion.

Later, work will start on a third major project, to build a new museum and library, housing artefacts and documents currently in storage.

Construction will begin by the end of the year, before the £500,000 complex opens in 2011 for the Great Western Society’s 50th anniversary.

Further projects are due to start next year.

A £65,000 broad-gauge engine shed will be built to house the National Railway Museum’s Iron Duke, which is to be relocated to Didcot where visitors can see it in action.

The move will house together the country’s only two broad-gauge replica engines, built to the specifications Isambard Kingdom Brunel originally intended.

The centre’s longer-term projects include revamping the centre’s entrance and disabled access, and extending the display track at the centre to include two new stations.

Roger Orchard, the centre’s operations manager, said: “Over 40 years, the centre has gone from being just a railway shed and water tower to a much bigger museum.

“The most frustrating thing for the society has always been not owning the site.

"We knew what we wanted to do, but didn’t want to do it until we had security here.

“We have had to put on hold a lot of development, especially new buildings. The fact is we have so much material we cannot display it all.”

Meanwhile some of the centre’s existing buildings, including the engine shed and water tower, need up to £1.75m of restoration work.

Mr Orchard said: “We need to do this work sooner rather than later because of the state of the buildings. We just cannot go on with them as they are.”