"Secret plans" to build a car park and toilet block as part of a housing development in countryside of historical and cultural significance will be the "final nail in the coffin for local heritage," shocked campaigners have warned.

Planning permission to build 800 homes and a primary school in Forster Country - land between North Road and Weston Road in Stevenage - has already been granted by Stevenage Borough Council.

Forster Country lies within the St Nicholas Conservation Area and includes author EM Forster's childhood home Rooks Nest House, Grade I-listed St Nicholas Church and Grade II-listed The Bury.

Now, permission is being sought by developers Bellway Homes and Miller Homes to build a 50-space car park and toilet block as part of plans for a country park on the development.

Hundreds of people had objected to the proposed housing development, with concerns including urban coalescence, loss of heritage, and the development being unsustainable.

"The council pushed the decision through by promising that the remaining fields would be protected and restored to the lush meadows lovingly described in Forster’s works," said a spokesperson for campaign group the Friends of Forster Country.

"Plans now brought for further approval include extensive construction to landscape the natural meadows, and to tarmac over them with a road, a major car park and a large toilet block, as well as adding gravel paths and bollards and an electrical grounding tower.

"The original master plan for the construction works put forward relied heavily on a restoration of the meadow and significant tree planting as justification for the development of the homes within the conservation area. There was no mention of a car park or a toilet block."

John Spiers, the campaign group's chairman, said: “You wouldn’t find a council building a car park on the West Yorkshire moors of Wuthering Heights or the Dorset vales of Tess of the D’Urbervilles. We are pained and baffled by Stevenage council’s failure to love Forster Country."

He warned that it "will be the catastrophic final nail for local heritage” if the plans are approved.

Emma Thompson, who won a Best Actress Oscar for her role in a film version of EM Forster's novel Howards End is supporting the Friends of Forster Country's campaign. She said: “To destroy beautiful countryside in aid of a car park is bad enough, but to destroy countryside with such a heritage, and of such value to the economy in terms of tourism, is sheer madness. It has to be re-thought.”

A spokesperson for the council said: “Far from there being a ‘secret plan’ for a new, exciting country park in the north of Stevenage, there will be open consultation so that all local people can have their say.

“To share the background, a planning application was received in 2017 for the development in the north of Stevenage. This included proposals for a new country park for all residents to access and enjoy.

"This application was approved by the council’s planning and development committee. Some elements, such as layout and landscaping, were required to be considered again in the future by the committee, through what is known as a Reserved Matters application.

“At the time, the committee made it very clear that the proposals for the country park must be of the highest of ecological and environmental standards, and respect local heritage including that of EM Forster.

“The council has received the proposed Reserved Matters application, including the proposed layout of the country park, and is carrying out public consultation. All residents are encouraged share their comments.

“We look forward to hearing your views on how, together, we can ensure this country park is an asset to the whole community in Stevenage, before the application is considered by the planning and development committee.”

The developers and council expect 500 of the homes to have been built by 2025.