Denmark’s richest man has made it his life’s work to restore the land, wildlife and buildings of his collection of Scottish estates to a more natural glory.

But now Scotland’s largest landowner has admitted a lifetime will not be enough to see the project to fruition.

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In a heartfelt open letter posted to his Wildland website, Anders Holch Povlsen and his wife Anne have revealed that they will pass their “rewilding” vision, along with their estates, on to their four children who will carry on the work after they are gone.

Although Mr Povlsen is only 46, while Anne is six years younger, they write of their responsibility for managing a dozen estates, covering more than 220,000 acres including Glenfeshie in the Cairngorms where they live.

“That responsibility has evolved to become a labour of love; a project that we are deeply passionate about,” they say. “It is a project that we know cannot be realised in our lifetime, which will bear fruit not just for our own children but also for the generations of visitors who, like us, hold a deep affection the Scottish Highlands.”

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Mr Povlsen, a clothing magnate who inherited the Danish retail chain Bestseller is estimated to be worth around £4.5bn. He is also the biggest shareholder in the British online clothes shop Asos.com and second biggest shareholder in its German counterpart Zalando.

The Wildlands project aims to restore native woodlands, peatlands, wetland and rivers to their natural state, while encouraging endangered animals and birds such as red squirrel, pine martens, Scottish wildcat, capercaillie and black grouse to thrive once again. Mr Povlsen has also stated that he wants to restore derelict properties, making the landscapes more accessible to visitors and aims to use the land to help educate children about the value of conservation. The letter also reveals the plans the couple have for individual estates in their portfolio, including Glenfeshie, Eriboll and Polla, Braegill and Hope, Gaick and Ben Loyal.

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“From our home at Glenfeshie, both Anne and myself – our children and our parents too – have long enjoyed a deep connection with this magnificent landscape,” they write, explaining that their love for the Scottish Highlands has grown with their greater involvement over the years, along with their understanding of the issues and opportunities that come with ownership. “As the holdings have grown and our common vision for the work becomes ever clearer, we have incorporated the entirety of the project into a venture we call Wildland,” they add. “It’s a significant and lifelong commitment that we have made - not just for ourselves but for the Scottish people and Scottish nature too - a commitment which we believe in deeply.”

They say that while individual initiatives may be complex, their vision is simple: “We wish to restore our parts of the Highlands to their former magnificent natural state and repair the harm that man has inflicted on them.” This applies not just to the land but to many of the buildings of which they are now custodians, they add. “There are many vulnerable properties across all of the holdings that we have the wonderful and privileged opportunity to rehabilitate and restore to life; there are also archaeologically important structures that we have the responsibility to protect.”

Meanwhile – although critics have claimed their projects so far have generated limited employment opportunities, they claim they are committed to the communities which they now see themselves as a part of. “Our vision of Wildland is of a project that provides security and an enduring connection, not just for those that work and live on our estates but also for the greater communities.” the letter says. “We are working towards an entirely sustainable model; everything in balance a project that can endure beyond what Anne and myself can ever expect to see in our own lifetime.”

Mr Povlsen has acquired a dozen Scottish estates – amounting to around one per cent of Scotland’s land – in little over a decade. He has been involved in controversies over the level of red deer-culling his plans appear to entail and was involved in a face off with the Scottish Government in 2016 over plans for a wind farm at Creag Riabhach in Sutherland – on land he does not own but which will be visible from several of his properties.

However he has also supported local causes. Most recently he gave a six figure interest-free loan to the Assynt Foundation, which is responsible for the 44,000-acre Glencanisp and Drumrunie estates after banks refused to loan the struggling foundation any more money.

Assynt Foundation executive officer Gordon Robertson said:”We made the approach to Wildland because we share similar values to the land as Mr Povlsen. He knows the area well. We showed them our projections and they liked what we are trying to do to look after precious landscapes. It is a lifeline. The money is banked and we’ve never been in a better position. The value of the estate has doubled from £2.9 million when we bought it.”

The Assynt Foundation used land reform laws in 2005 to force the wealthy Vestey family to sell the Glencanisp and Drumrunie estates in Sutherland and Wester Ross. The Scottish Government blocked the sale to allow the foundation to buy the land in the £2.9 million deal, which was funded by donations, government money and lottery funds.