DIDCOT Railway Centre has revealed major expansion plans after securing its future in a deal with Network Rail.

At the end of last year, the site owner agreed to give the Great Western Society a 35-year-lease for its home next to Didcot Parkway station, where the steam train collection has been housed since 1967.

The centre, which attracted 50,000 visitors last year, has previously only had a rolling six-month lease, making it difficult to attract funding for development.

The deal with Network Rail means the centre can press ahead with expansion and show more restored steam engines.

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

The first development this summer will be a new 180-feet-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 building steam engines inside passenger coaches. The company ripped the power units from the carriages in the 1930s, so when the restored Steam Railmotor 93 goes on display in its new home, it will be unique.

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

Work will start on a third major project, to build a new museum and a library for 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 new £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 will be able to see it in action.

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

The centre’s longer-term projects include a revamp of its entrance and disabled access, and extending the display track to include two new stations.

The centre’s operations manager, Roger Orchard, 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.”