 |
|
Thirlwall Castle
 |
We provided the professional lead for the conservation of Thirlwall Castle, near the village of Greenhead in Northumberland. A picturesque ruin set on a spur overlooking the Tipault Burn in the outstanding landscape of the Northumberland National Park. Close to Hadrian's Wall, Britain's most important Roman monument, Thirlwall was constructed in the fourteenth century by John de Thirlwall using stones 'robbed' from the Roman wall and nearby milecastle. Disused by the mid C17, it became a ruin over the next hundred years.
The ruined castle provides a physical link with the two most important historical periods in the North of England: the Roman occupation (c.54-409) and the Border wars between England and Scotland (c.1296-1545). Besides being a significant part of Northumberland's cultural heritage and part of the Hadrian's Wall UNESCO World Heritage Site, it is located in an area important for tourism, on the Pennine Way and Hadrian's Wall long distance walking routes. It is also ecologically significant as a wildlife habitat and a geological Site of Special Scientific Interest.
Our work included preparing a condition report, conservation plan and access audit, taking the lead in a range of other investigations to inform the proposals, and providing full architectural services for consolidating and restoring it as a visitor attraction. The castle has been a ruin for some 300 years, subjected to ground movements, stone robbing, progressive decay and erosion by the elements, and the effects of uncontrolled vegetation. It survival was directly attributable to the massive stone construction and the Roman stones used by the medieval builders, which have tails embedded up to 400mm into the wall core. Nevertheless, major conservation works were required to stabilise and consolidate it:
 |
 |
|
 |
 |
 |
 |
 |
 |
A key feature of the project was researching and designing methods of integrating natural and built heritage aspects, so that communites of Swifts, bats, and rare lichens and wall plants could be preserved. The conservation work also included researching and restoring a lost window opening and various sections of walling to provide structural support in a harmonious way, as well as grouting, repointing using lime based mortars, and innovative 'soft' wallhead treatments using the original vegetation to preserve the natural appearance of the monument. It is visited by many schools and walkers, and we have maintained our involvement with the monument by returning to carry out two quinquennial inspections and advise on long term maintenance. The project won a Civic Trust Commendation.
To link to the Northumberland National Park's website click here.