The £3.8 million community buyout, the largest ever in the South of Scotland, comes after successful negotiations between the Langholm Initiative charity and estate owners Buccleuch.
The move, which was finalised after the landowners agreed to drop the selling price, paves the way for the creation of a huge new nature reserve to help tackle climate change, restore nature and support community regeneration.
It comes following an ambitious community fundraising campaign, including £1 million from the Scottish Land Fund.
Other major funders include South of Scotland Enterprise, John Muir Trust, Carman Family Foundation and Garfield Weston Foundation.
During the final week of fundraising, an extraordinary surge of more than £50,000 in donations to the charity’s public crowdfunder – including £24,000 on one day alone – saw the appeal’s £200,000 target achieved by the 31 October deadline.
Nearly 4,000 people have supported the crowdfunding appeal since its launch on 7 May.
The purchase – to be finalised by January 2021 – will lead to the creation of the Tarras Valley Nature Reserve, with globally important peatlands and ancient woods restored, native woodlands established, and a haven ensured for wildlife including rare hen harriers.
The project will also support community regeneration, including plans to capitalise on new nature-based tourism opportunities.
Discussions over the buyout of an additional 5,300 acres of land from the estate are continuing.
Scottish environment and land reform secretary Roseanna Cunningham said the deal marked “a momentous moment for land reform in Scotland”.
“I commend both the Langholm Initiative and Buccleuch Estates for enabling the buyout to be completed.
“This is significant news for the South of Scotland but also demonstrates that, when working together with a shared goal, local communities can be a power vehicle for change.
“I applaud the initiative wholeheartedly for realising their ambition and look forward to it inspiring other community groups to drive and deliver their own projects right across the country.”
Margaret Pool, chair of the Langholm Initiative, said: “This is an amazing result for Langholm which will live long in the memory.
“Our community has a strong cultural connection to this land, which has never been sold before, and securing it for generations to come means so much to so many.
“Huge thanks to Buccleuch for their positive engagement.”
Benny Higgins, executive chairman of Buccleuch, said: “We’re absolutely delighted to have reached a significant agreement with the Langholm Initiative, and this deal demonstrates what can be achieved when everyone involved is committed to working together.
“The community has done a tremendous job in raising the funds to make this historic acquisition, and the plan to create a nature reserve has attracted widespread support.
“We wish the project every success.”
The Langholm Initiative, formed in 1994 as one of south Scotland's first development trusts, facilitates projects making a lasting difference to the local area and people.