Save the World’s First Garden City campaigners turned out at a Heritage Foundation exhibition on Friday to highlight their concerns over plans to build homes to the north of Letchworth’s Grange Estate.

Members were invited to the demonstration by the group’s chairman so they could make their voices heard ahead of the last day of the exhibition.

The Heritage Foundation’s display was made up of plans put forward by various architects who had entered into the organisation’s competition to create a concept for a ‘modern garden city’.

The ‘Re-Imagining the Garden City’ competition was opened internationally to architect-led design teams in October last year.

The Save the World’s First Garden City letter read: “Some of us on the committee have decided to visit the Exhibition of Architect’s Design for Local Plan site LG1 – north of the Grange Estate.

“The object is to make whoever is there at the time aware of important issues: this is an important wildlife site with recorded presences of 84 endangered species and also part of a nationally important wildlife corridor.

“By anybody’s definition a large development on this location represents ‘urban sprawl’. Not only is this Green Belt, but prototype Green Belt – Ebenezer Howard’s ‘Agricultural Belt’, a key part of his vision of sustainability, therefore of historical significance.

“The Heritage Foundation exhibition pre-empts the government inspector’s decision on the Local Plan. It might not be passed!”

The Heritage Foundation received 95 entries from architectural practices around the world, using the proposed housing development site to the north of the Grange Estate as a case study.

Graham Fisher, the Heritage Foundation’s chief executive, said: “We are really pleased that there has been an excellent response to our design competition, with nearly 400 votes and hundreds of comments, as part of a community consultation.

“The purpose of the competition is to contribute to the debate about modern garden city living and generate initial thoughts for the land to the north of the Grange.

“We are also starting the next phase of community engagement to discuss with the local community how we ensure that if this development proceeds, it is of the highest quality. However, we will only submit a planning application for this development, if the statutory process confirms the inclusion of this land in North Herts District Council’s Local Plan.

“Matters concerning Green Belt, countryside and housing requirements were discussed at length in the public examination held by the government inspector and we have already undertaken significant work in order to understand possible impacts and opportunities in greater detail.

“We have been undertaking detailed on-site ecological investigations since October 2017 to understand how we can design a scheme that minimises any impact. We look forward to producing an illustrative plan for further discussion with the local community, once we have completed this stage of research and engagement, and there has been further progress in the Local Plan process.”

North Herts District Council’s Local Plan is currently being looked at by a planning inspector, who advised the council on a number of modifications in January this year.

Campaigners have put in a request to the planning inspector to reopen the Local Plan public hearings.