The last 100 tickets are still available for the first steam train to travel over the Leiston branch for about 60 years which is due to run next April.

The special train, organised by Ipswich-based Charity Railtours, will see steam locomotive Mayflower hauling the train from London up the main line to Ipswich before travelling over the East Suffolk Line to Saxmundham and then to Leiston on the freight-only branch that serves the Sizewell nuclear site.

The Leiston branch is all that remains of the Aldeburgh branch line that was closed to passengers in 1966 following the publication of the Beeching report – the last four miles were taken up shortly after the end of passenger services.

The charity railtours train will run on Sunday, April 15. It will start from London and pick up passengers in Colchester before travelling on to Leiston. It will also travel on freight-only branches at Griffin Wharf in Ipswich and at Harwich before returning to the capital.

Dennis Barnes from Charity Railtours said it was believed to be the first passenger train to use the Leiston branch since 2002 or 2004 when a diesel enthusiasts’ special visited the line.

He said: “This is a very special trip and we have had a great deal of interest. We do still have about 100 standard-class seats left but we are expecting they will go quite soon.”

The trip is raising money for Macmillan Cancer Support and is the second time Charity Railtours have brought steam back to unusual lines in the area.

Mayflower is owned by businessman David Buck who was born and brought up in Ipswich but now lives near Windsor.

It was a conversation with him that led Mr Barnes to organise the unusual tour – Mayflower is a B1 class steam locomotive which regularly pulled trains in the region until the 1950s.

He said: “I was talking to the engine’s owner and he said he would love to bring it back to some of its old haunts – so we started putting this together.”

Mayflower returned to the main line for the first time in nearly 50 years in 2015 and has been undergoing an intermediate overhaul over the last few months – but is now being tested before returning to steam early next year.

Full details of the trip and a provisional timetable, which is subject to confirmation, are here