View 1965 film of a train coming into Okehampton (Michael Clemens)
The Okehampton to Exeter Railway Line - last used by passenger services in 1972 - could be re-opened again.
There are plans to operate several trains a day on the line starting from late May 2010.
Devon and Cornwall Railways (DCR) wants to launch the service from 23 May. There would be six return journeys each day, seven days a week.
"We hope it will be used by commuters getting into Exeter," said Mike Fairburn, managing director of DCR.
"It's a very scenic route through the countryside and on the northern side of Dartmoor so it is also a nice journey for day trippers.
Okehampton station as it is now - it was restored in 1997
"There is a lot to do yet but we've got the locomotive and carriages. We are now working on the legal requirements and access."
The trains would run every 90 minutes, with three carriages allowing capacity seating of around 130. There would be stops at Okehampton, Sampford Courtenay, Crediton, Exeter St David's, with some services going on to Exeter Central and St James Park.
The line - known as the Dartmoor Railway - was built in the 1860s and 1870s and Okehampton Station was opened in 1871.
It is hoped that a service from Okehampton to Meldon Quarry will also be possible, taking passengers right to the edge of Dartmoor.
The Exeter to Okehampton passenger service was axed by British Rail in 1972, but the line remained to allow freight transportation from Meldon Quarry.
In 1997, a summer passenger service, backed by Devon County Council, was brought in for day trippers on Sundays.
DCR is hoping there will be enough passengers to sustain daily services.
A train pictured heading towards Okehampton in 1965
"We are starting this service at our own cost, " said Mr Fairburn.
"We hope it will break even and then make a profit, in time."
He added: "We are absolutely delighted that the railways are making a comeback.
"It's a reflection of the changing times when it comes to travel and attitudes to the environment.
"There are many advantages to travelling by rail. You can leave your car at home, and this line will improve transport connections."
Final approval for the planned new service is needed from the Office of Rail Regulations, and DCR will require a train operator's licence and safety certification.
A spokesperson at Network Rail said: "We welcome the aspirations to introduce new services on the line and are working closely with Devon and Cornwall Railway to examine the feasibility of their proposals."
* The archive film on this page and the archive images, courtesy Michael Clemens.