The sunlight glinted on the little waves as they chased each other across the water.

In the foreground a sign announced that this was the Malham Tarn National Nature Reserve. The path I'd been
walking from Malham village was waymarked with white acorn signs indicating that this was a national trail – the Pennine Way, in fact, the grandfather of them all and still regarded by many as the one long-distance walk to do above all others.

All around was the remarkable limestone scenery for which the
Yorkshire Dales National Park is famous. Many will have done this same walk and enjoyed the same things through the freedom to roam across a wonderful natural landscape.

The man-made elements – the moorland sheep farms and the zig-zagging miles of drystone walls – add to our pleasure and rare plants, animals and birds can be seen because they have been protected and encouraged.

It's 60 years this month since the National Parks and Access to the Countryside Act was passed. It opened the gate to the creation of our national parks, their sisters the Areas of Outstanding Natural Beauty (AONBs), national nature reserves and national trails. It was arguably one of the most important pieces of legislation in the 20th century, one that has shaped – in a small way at least – all our lives.

Yorkshire was to do particularly well out of it. No other county can now rival the amount of land protected, promoted and enhanced in one way or another.

In the 1920s and 30s there was a growing clamour from the many who were excluded from swathes of beautiful and rugged upland landscapes by a few landowners determined to protect their farming and shooting rights.

Those years climaxed in 1932. Early in the year some hikers from Manchester were stopped by gamekeepers at Bleaklow in Derbyshire for trespassing. Not long after, on April 24, the hikers returned in numbers – about 400 – for what became known as the Kinder Scout Mass Trespass on land owned by the Duke of Devonshire.

It ended with some violence, arrests and even imprisonment. The publicity probably helped to swell the growing ranks of ramblers' clubs, the Youth Hostel Association, and of organisations like the Council for the Protection of Rural England and the Co-operative Holiday Association.

A teachers' union talked excitedly of emulating how the Germans were giving their young a love of the countryside. It was the Hitler Youth they had in mind. Not much more was heard about that.

Other countries, such as America, had already created national parks, the first, Yellowstone, in 1872. Their national parks were on land owned by the state and that was the example that many people wanted to follow here. But it soon became clear that our version would be a very British compromise involving the people who owned and worked the land.

The delay and inaction seemed just as typically British. The first report into the idea, by the Addison Commission, came out in 1931. It was followed by a lot of talk and paperwork but not much else.

The Dower Report of 1945 reignited the idea. It laid down what the duties of a national park should be and two years later, in 1947, the Hobhouse Report identified 12 areas that should become national parks. With the recent designation of the South Downs, all 12 have now been brought into being.

John Dower, a Yorkshire architect from Ilkley, was the man who defined what a national park ought to be – "an extensive area of beautiful and relatively wild country in which, for the nation's benefit and by appropriate national decision and actions, (a) the characteristic landscape beauty is strictly preserved, (b) access and facilities for public open-air enjoyment are amply provided, (c) wildlife and buildings and places of architectural and historic interest are suitably protected, while (d) established farming use is effectively maintained."

The AONBs were to have the same powers to preserve the environment,
but were not felt to offer the same opportunities for outdoor leisure.
Public access in general was to be promoted and national trails created. This was to take some time to bring about. It was not until 1965 before the first, the Pennine Way (which had initially been promoted in a newspaper article in 1935), became reality. The 109-mile-long Cleveland Way, our second national trail, opened four years later.

No doubt to the great joy of the surviving mass trespassers, the Peak District became the first national park in 1951. Yorkshire was second in line, with the North York Moors in 1952; the Dales followed in 1954.

Many battles had to be fought along the way and committees met interminably. Should this village be included within the park boundary, should that town be left out?

Widespread opposition was met from farming and landowning interests. Boundaries which began as clear lines on the map (like the rail line along the southern side of the North York Moors) became contorted as lobbying from some of the more powerful landowners succeeded in keeping their estates outside the limits.

There was also the no small matter of deciding what powers the new park authorities should be given and who should appoint them. These were ironed out pragmatically as the parks gradually came into being.

So 60 years on, how have they done?

The North York Moors spreads itself over 554 square miles of rolling moorland and sheltered dales. It has has a population of 25,000, takes in 846 scheduled ancient monuments and 42 conservation areas, and attracts 6.3 million visitors a year who spend £317m. It's a big business.

Even bigger – 685 square miles – is the Yorkshire Dales where almost 20,000 people live. Annually it plays host to 9.5 million visitors who spend about £400m.

Altogether this is £1bn a year industry for Yorkshire if you add in the money from the Yorkshire section of the Peak District near Sheffield and Huddersfield and the Nidderdale and Howardian Hills AONBs.

The ravishing photographs of these dramatic landscapes are some of the most powerful marketing tools that we possess for persuading outsiders to invest in Yorkshire. Some may think this good news business story means that the case for the success of national parks is beyond argument.

Or would those idealistic campaigners from the 1930s, who weren't quite as materialistic, have shuffled their big boots and felt a little uncomfortable at the way things have turned out?

Standing, pint in hand, outside the Lion on Blakey Moor looking out over the hills and dales of the North York Moors (or doing the same at the Hill Inn at Chapel-le-Dale near Ingleton in the shadow of two of the Three Peaks, or at the Riverhead Tap in Marsden), I think they would have been very satisfied.

Progress towards one major aim, landscape protection, would have delighted them.

By and large it has been excellent. The great quarries still working at Horton-in-Ribblesdale and other places and the huge mast built on the hills above Bilsdale would have vexed them however. The old idealists would also have been delighted by the enormous improvements in access and by our national trails. The fact that sections of them – the Pennine Way in particular – have had to be paved because of overuse would have amazed them.

On plant and wildlife, their verdict would have been mixed. Some species are much more common now; others sadly not so. A glance at the magnificent stands of globeflowers at the Ingleborough National Nature Reserve or the peregrine falcons at Malham Cove would have evoked the same feelings of wonder as they do in us today.

But they'd be less happy at seeing farmers further down the dale ploughing flower-rich turf to re-seed it with monotonous "agri-grass".

They would have approved, I'm sure of the network of visitor centres, loved the Dales Countryside Museum alongside the national park centre at Hawes and been delighted by the many interpretive panels and trails explaining how the landscape grew up and telling us about its wildlife and the lives of the people who used to work there.