There could be no more fitting present for the 1949 National Parks Act on its 60th birthday than the Isle of Harris's decision to join the pantheon of Britain's greatest landscapes. But celebrations are far from complete, with the battle for the South Downs still to be won.

From the outset, national parks challenged the traditional landowners' consensus: the countryside was a place of crops and cash. The historian G.M. Trevelyan thought the parks “a question of spiritual values”. His kinsmen felt a desperate longing “for natural beauty and the great unspoilt spaces”. It was a way to say sorry for the Industrial Revolution, giving urban labourers the same right to the natural heritage as any country squire. It was a conviction that the working classes themselves acted upon in 1932 with the mass trespass on Kinder Scout.

Interwar planning laws risked destroying that very heritage under a morass of car parks, cafés and bungalows. Stanley Baldwin could say that “to me England is the country and the country is England,” but his laissez-faire approach let electricity lines, ribbon developments and new roads rip through the countryside.

The solution was a system of government protection for nationally significant landscapes that would open them up for outdoor pursuits, free from the landowners' guns and gamekeepers. Close to big conurbations and encompassing large tracts of wilderness, national parks promised sublime landscapes and “the refreshing qualities of air and climate and the active pastimes of the countryside.” The focus was on pleasure for the people, rather than a landscape for the leisured classes.

During the war, home-front propaganda had appealed to a green and pleasant ideal of England. Suddenly, Britain was its lakes, peaks, coastlines and moors. And the incoming Labour Government was riddled with ramblers determined to liberate the countryside. Of course, implementing the 1949 Act was another thing - to establish the Peak District park in 1951, Hugh Dalton had to overrule the reactionaries on Derbyshire County Council. Since then landowners, quarry companies, farmers and councils have kept on objecting.

The people of Britain will now have the white beaches, romantic hills and unrelenting rain of Harris to add to their enjoyment.

But the final prize must be the inclusion of the South Downs in our necklace of national properties. The squires and megafarmers of Sussex must forget fears about ramblers and regulations and open up their countryside. As Wordsworth said of the Lakes: “Every man has a right and interest who has an eye to perceive and a heart to enjoy.”

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