The Second World War casts a long shadow in the Netherlands. Its legacy of destruction is there in the tidy rows of houses that sprang up to replace the bombed-out shells and in the immaculately-maintained cemeteries.

But there's a happier legacy, too, in the unforced affection of the Dutch people for the nations that liberated them from Nazi occupation and in the awareness of the young, who are taught what their country endured and so have a passionate appreciation of what it is to live in freedom.

Everybody here knows the story of how Holland was liberated after five brutal years and at what terrible cost. Every year, in the third week of September, when the dwindling band of veterans make their pilgrimage back to Arnhem, close to the German border to remember the epic, doomed Operation Market Garden, local people gather to applaud them and children place flowers on all 1,763 graves in the cemetery at Oosterbeek. And now, it seems, the story of heroism, sacrifice and suffering is rippling out from the young people of the Netherlands to those of Britain, Germany and beyond.

That's because, to the surprise and delight of the tourism people around Arnhem and Nijmegen, visitor numbers are not only on the increase, but the average age of the visitors is going down.

The battlefield trail in this attractive, forward-thinking part of Holland is worth between three and four million euros a year, and brings in 250,000 people annually. But that's not the only story. The average age of the visitors is 32 and the museums are full of children wide-eyed at the stories unfolding before them. Four years ago, the authorities put on a magnificent show for the 60th anniversary of Market Garden. It was a glorious, flag-waving occasion, in which veterans marched across the bridge at Arnhem built to replace the one destroyed in fighting.

It was a salute from Holland to the men who had fought so courageously. It was also a tacit acknowledgment that this was a last hurrah and there could never again be a commemoration on this scale involving those who were there.

But now, 64 years on from the biggest airborne assault in history, when 35,000 British, American and Polish troops tried to bring the war to an early end by seizing five key bridges that would open an invasion route to Germany, the growing interest among the young in what happened has driven the creation of a new series of memorials.

The Liberation Route is the first stage in what will eventually become a vast trail of monuments stretching from the beaches of Normandy where Allied troops came ashore on D-Day, June 6 1944, all the way into Germany.

For now, it comprises 23 stone memorials at the sites of key events. Arnhem is there, of course, hard by the site of the Bridge Too Far, but so too are lesser-known, but no less vital points on the road to liberation.

There is Gennep, where British engineers built the longest Bailey Bridge – brainchild of Rotherham's steel mills – of the war to get troops and tanks over the River Maas, a feat so spectacular that Churchill made a special trip from England to see it.

Wijchen, where the first black American troops landed, is marked on the route, as is Klein Amerika, where US paratroops filled the skies as they floated to earth.

The British landing ground at Renkum, where forces were hailed as conquering heroes before a shot was fired, is a key location, as is Driel, where Polish soldiers fought like tigers to rescue embattled comrades.

This is not just a trail that commemorates the battle for the bridges around Arnhem and Nijmegen.

It takes the story forward into one of the bloodiest, yet least-remembered, episodes of the war, Operation Veritable, which finally freed Holland and opened the road into Germany.

Veritable started in February 1945 and soon became bogged down by atrocious weather into horrors that commanders thought had been left behind in 1914-18.

Men drowned in the mud and armoured vehicles sank without trace as the Germans fought a ferocious last stand. But the Allies persevered and in April 1945, Arnhem was liberated by the West Riding Regiment.

Those soldiers would hardly believe the technology being used to tell their stories today. Visitors can telephone each memorial stone to hear a narrative of what happened there, told by actors, download an audio tour to an MP3 player, or programme the locations into a sat nav. The technology – and the 350,000 euros it has taken to establish the Liberation Route – makes for a neat fit with the Arnhem and Nijmegen of 2008. This area is Holland's answer to Silicon Valley. Booming
hi-tech industries have given the area the highest economic growth and the lowest unemployment in the Netherlands, with easy access to both the great ports of Rotterdam and Antwerp as well as Germany. Conveniently for the battlefield trail, the growing urban area is surrounded by greenbelt, where much of the story of the fighting unfolds. The two cities themselves would be worth visiting even without the history that drives their tourist trade. Arnhem is a vibrant place, where the restored Eusebius Church with its dizzying views from the spire is a must-visit. Nijmegen, with its cobbled streets, magnificent cathedral and bustling market, is no less attractive.

But it is the wartime legacy that lures the visitors, and the detail of what happened is there in the two main museums. The Airborne Museum is at the former Hotel Hartenstein, in Oosterbeek, where the British made their headquarters during the battle for Arnhem, and the National Liberation Museum is a few miles down the road at Groesbeek, in a striking building in the shape of a parachute canopy. They are both getting busier. The director of the Arnhem-Nijmegen Regional Tourist Board, Jurriaan de Mol, said: "We thought interest would die out, but it isn't. It's growing. When we started this project last year, I was telephoned and emailed by hundreds of people with their own stories or their suggestions about what we should include. This theme is still very much in people's hearts.

"We discovered that the average age of visitors is 32 and the museums are telling us that there is a lot of interest and attention from young people who want to know what happened. About 50 per cent are interested in the military history and 50 per cent are interested in what happened to the civilians."

So there's an abiding interest in what happened here and for the cities of Arnhem and Nijmegen a valuable source of revenue. But here, in the heartland of what was occupied Europe, it's about much more than commerce. This is about patriotism, gratitude and affection.

The gardens of the houses that line the roads are still full of orange flowers, just as they were during the war years when the Dutch people grew blooms in their national colour as a symbol of
resistance, and a reminder of their national identity.

And on the road down to the old church at Oosterbeek, on the banks of Rhine, where the British survivors of Market Garden were evacuated under cover of night, the houses still fly Parachute Regiment flags all year round. And that's got nothing to do with how many millions the tourists bring in.

P&O Ferries' service from Hull to Rotterdam provides the ideal gateway to the Liberation Route. Details at www.POferries.com or call 08716 646464

Details of the Liberation Route can be found at www.liberationroute.com

The Arnhem-Nijmegen Regional Tourist Board can be found at www.vvvarnhemnijmegen.nl