The year started with a Valentine’s Day heritage hug, a protective ring around the Iron Age hillfort of Old Oswestry, in North Shropshire, under threat of housing nearby. But 2015 is set to end in bitter protest as campaigners descend on Shropshire Council’s seat of power where it is due to approve the ‘hillfort estate’ on its local plan.

On December 17, defiant campaigners will stage a demonstration at Shirehall, Shrewsbury, as councillors arrive to ratify SAMDev, Shropshire’s planning blueprint to 2026. It includes a fiercely opposed site for 117 houses (OSW004) that will breach a long-respected town boundary triggering further urban enclosure of the scheduled hillfort.

Organised by HOOOH (Hands Off Old Oswestry Hillfort), the demonstration is being publicised via the group’s national network of supporters and a social media campaign #InDefenceOfOldOswestry.

It follows Inspector Claire Sherratt’s verdict after examining SAMDev that OSW004 would “lead to less than substantial harm to the significance of a designated asset.”

Historic England and Shropshire Council have both come under fire from campaigners for signing a statement of common ground agreeing to development subject to master-planning conditions.

HOOOH member Neil Phillips said: “Shropshire Council may be hoping to sign over our heritage to the bulldozer and escape the fallout during the Christmas break. But we have a prominent legal firm briefed and ready to launch a judicial review if OSW004 remains in SAMDev.”

He continued: “The Old Oswestry campaign has never been a Nimby or anti-housing protest. It has only ever been about the heritage. During consultation, stakeholders including Oswestry Town Council asked Shropshire planners to review housing sites in Oswestry and implement better protection for the hillfort setting, but they have refused.”

Campaigners say that Shropshire Council is making Old Oswestry an unnecessary victim of over-ambitious housing targets which do not reflect local demand yet are giving developers leverage to target the most precious spaces.

“This is a fight by the community to protect a much loved place of escape and recreation, and an asset of immeasurable heritage, community and tourism value,” said campaigner John Waine. “It is also a national fight to protect the rightful territory of one of Britain’s most important hillforts which, incredibly, is at risk under the new NPPF. A loss at Old Oswestry could see diggers bearing down on landscapes of heritage, environmental and cultural importance across the country.”

The proposals have been opposed through several stages of consultation by thousands, including residents across Shropshire, local stakeholders, prominent heritage experts, national organisations and concerned observers around the globe.

Professor Lord Renfrew of Kaimsthorn, Professor Sir Barry Cunliffe and other eminent archaeological academics wrote an open letter last December to the UK government objecting to OSW004. They state: “If the bar for acceptable development under the NPPF does not protect the setting of even our most significant heritage sites, then we set a potentially calamitous precedent for the greater part of the nation’s historic environment.”

HOOOH says that the December 17 demonstration is also about failed localism. While the hillfort site has attracted overwhelming opposition, Oswestry residents are still facing the prospect of development within one of their most valued neighbourhood spaces.

Maggie Rowlands of HOOOH said: “Ratifying OSW004 on Shropshire’s local plan is a golden ticket to build, for which each and every Shropshire councillor will shoulder responsibility. If this housing estate goes up, we will be reminded every day of their decision to ignore the overwhelming consensus of the public and the most qualified opinions of British archaeology. Every day, local electors will be hit in the face by their legacy – a growing wedge of bricks and concrete obliterating the ancient green landscape intrinsic to the hillfort’s value and beauty.”

She added: “It is not too late to say ‘no’. Local stakeholders are keen to sit down right now to resolve housing delivery which doesn’t jeopardise this national treasure of British heritage.” The ‘In Defence Of Old Oswestry’ demonstration takes place at 9am on Thursday 17 December on the steps of Shirehall, Shrewsbury. HOOOH is urging people to sign up and follow the countdown to the protest on Facebook.