A set of 18th century coach house and stable buildings – along with a six acre plot of woodland – has sold for almost half a million pounds, with local residents who have been looking after the land saying they are keen to work with the new owner.

The coach house and stables, which were once part of the large Wick House Estate in Brislington, were sold this week for £452,000 at an auction – it was the first time the buildings and the land for 100 years after the estate was broken up back in 1924.

The identity of the buyer, known only as ‘Mr K’, is unknown, but the Friends of Brislington Brook, the volunteer group of nature lovers who have been looking after the woodland in the Nightingale Valley for more than 20 years, say they want to work with him to devise a plan for the future of the woodland behind the coach house that drops steeply to the brook below.

The land in question is littered with hundreds of metal barrels of tar or bitumen, which begins to seep into the ground and down the hill with every heatwave, but have never been cleared up since it was dumped there, probably back in the mid-1920s.

Amid fears that the sale could bring in a new owner keen to clear the woodland and develop, or close off public access, the Friends of Brislington Brook are mounting a two-pronged strategy to protect the wood and the paths.

One volunteer with the Friends group made an application to the city council last month to have Tree Protection Orders placed on some of the trees – and this week the council confirmed to the applicant that an order protecting all the trees on the land has been served on the new landowners. A consultation will be launched within weeks and people will be given the opportunity to object, before the TPO is formally brought in next year.

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At the same time, another of the volunteers with the group has submitted an application to have the ‘Pilgrim’s Path’ through the Nightingale Valley, which crosses the Wick House coach-house land, adopted as a legal right of way. That process can take years, and requires people to provide evidence that the path has been used for decades without a break.

“We’ve done everything we can to protect the flora and fauna in Nightingale Valley and to keep the footpath open,” a spokesperson said.