Knott made his fortune in the Prince Line shipping company, and his life held the kind of tragedy that often shapes large bequests. Two of his three sons were killed in the First World War. He spent his later years on philanthropy and died in 1934, leaving £5,000,000 to a charitable trust. College Valley Estates Ltd, the company the trust created, purchased the estate - roughly 12,000 acres of the northern Cheviots running south from Kirknewton toward The Cheviot itself - at auction in 1953. The trust still funds the company that runs the place today. The estate's stated duty is to manage the valley as a place of environmental, social, and economic excellence - which in practice has meant treading lightly. Limited permits. Limited buildings. Sheep, but not too many. A board of directors, but no profit motive louder than the wider purpose.

The valley has been inhabited for a very long time. Bronze Age forts ring the hilltops above the estate - Great Hetha, Sinkside Hill, and others - testimony to a settled population working these uplands three thousand years ago. Iron Age successors built on top of them. Evidence of medieval habitation runs back to the thirteenth century at Hethpool. The estate office today sits at Hethpool House, and a small cluster of estate cottages built in the Arts and Crafts style stand nearby. Hethpool Mill, once driven by the College Burn, has been converted into self-catering accommodation. None of this is theme-park heritage. The cottages are still lived in or let; the mill still has its leat; the forts are just lumps in the turf on the high ground that nobody is in a hurry to dig up.

Before Sir James Knott, the College Valley had passed through ownerships that read like a roll call of the British establishment. Cuthbert Collingwood, 1st Baron Collingwood - Nelson's second-in-command at Trafalgar, who took over the British fleet after Nelson was killed - owned the estate in the early nineteenth century. From the Collingwoods it passed to the Grey family of Howick Hall, the same Greys who produced Charles, 2nd Earl Grey, the Prime Minister whose government passed the Great Reform Act of 1832 and whose name lives on in tea. Arthur Sutherland, a shipping man like Knott, held it next. The valley is private, but it has been private in the hands of public figures - admirals, prime ministers' relatives, shipowners - for two centuries.

The road enters the valley at Kirknewton on the route between Wooler and Kirk Yetholm and splits almost immediately - right hand fork to Trowup burn, left hand fork past the estate office and up the main valley. Where the valley itself splits, near the foot of the highest ground, the right fork climbs to Mounthooly, now a Youth Hostel Association bunkhouse, and the left climbs past Coldburn Cottage and Dunsdale House toward Goldsceugh. From here the ascent of The Cheviot - 815 metres, the highest hill in Northumberland - is the long approach the valley name promises. Hills line the route on both sides: The Schil at 600 metres, Black Hag, Scald Hill, Newton Tors, Preston Hill. The walking is open. The driving is restricted. The arrangement, by design, costs the valley its convenience and gives it back its quiet.