From the glittering Havel River, the city of Potsdam appears to float like a dream – a vision of palaces, pavilions, domes and towers rising above the trees and clipped lawns.

Beside the water, students lie on the grass laughing, couples embrace, and sharply-dressed office workers enjoy the sunshine before returning to the hi-tech and media companies which are transforming this historic gem into Germany’s creative powerhouse.

It’s hard then, to imagine that not-so-long ago, this was a killing zone.

Exactly 60 years ago this week, the Soviet-puppet state of the German Democratic Republic surrounded the Allied-zones of West Berlin with a 160km wall of concrete and barbed wire. Intended to stem the flow of skilled labour to the West, the East German state reinforced its message with landmines, armed guards, searchlights and ferocious dogs.

With the river marking the border between West Berlin and the GDR, Potsdam found itself right on the fault line. And few of those who chanced an illegal crossing lived to tell the tale.

“This was the Death Strip,” says Oliver Gondring, who now takes curious tourists on cycle tours of the Berliner Mauerweg – Berlin Wall Trail – which follows the course of the old ramparts.

“It was a very dangerous place, and no one was allowed to come close,” he says wistfully. “Though many tried to cross, only a brave few people succeeded.

“Of course, now it is very beautiful. It is a green ribbon and we love it.”

It is the tantalising traces of that slightly surreal era which make this quirky capital of the state of Brandenburg a magnet to anyone with a love of history, or simply of Cold War spy movies.

Here and there are surviving, sections of wall, while grand buildings hide their murky past as KGB interogation centres, prisons and villas for the party faithful.

Spanning the river is a familiar Cold War icon: the Glienicke Bridge – or ‘Bridge of Spies’ – where captured Western and Soviet agents were secretly exchanged, as immortalised by Michael Caine’s Harry Palmer in the 1966 film Funeral in Berlin. Even crossing it now, on a sunny day, it’s impossible not to feel a frisson of excitement – as if you are a double agent on a mission.

Nowhere is the past so close to hand, however, as at Schloss Cecilienhof.

This incongruous English mock-Tudor style mansion in grand gardens was the unlikely setting of one of the defining moments of 20th century history – the 1945 Potsdam Conference, at which Stalin, Truman, Churchill and Attlee sowed the seeds of post-war politics by carving up the map of Germany.

And the ghosts are everywhere. From the courtyard, with its flower bed still planted out into a red star, to the creaking staircases, the weight of history is palpable.

It is a more distant, and romantic, history, however, which attracts most visitors to Potsdam today.

In the 18th century the city was chosen by King Frederick the Great as his Royal residence. And he set about transforming it into something suitably regal – the Rome of the North.

The rococo palaces, pavilions, formal gardens, follies, and fountains he left behind, eclipse Versailles, Blenheim and Vienna in their beauty, mixing the sublime and ostentatious. Understated they are not.

The Italianate palaces of Sanssouci are quite simply unmissable, offering a glimpse into a life of opulent discomfort – a world where appearances counted for everything.

It is all most un-Germanic, which makes it all the more joyous.

The crowning glory is the incomparable Pfingstberg – a riotous hilltop confection of columns and arches arranged around a pool, and crowned by towers affording eye-popping views over Brandenburg’s forests, and all the way to Berlin’s Alexanderplatz television antenna.

Off-limits during the days of the GDR, it has recently been restored and looks strangely brand new, which only adds to the sense of the surreal. It’s not hard to see why the whole lot has been given UNESCO World Heritage Site status.

But Potsdam is not all Cold War intrigue and rococo splendour. There is an altogether cooler side to this city, which once saw it home to some of Europe’s biggest stars.

Just out of town are the Babelsburg film studios – where Greta Garbo and Marlene Dietrich smouldered, Fritz Lang made Metropolis, and Josef von Sternberg shot The Blue Angel.

They have never stopped making films here, and it is thick with nostalgia. During the days of the GDR, Babelsburg continued to turn out high-quality cinema, with fascinating propaganda films, and wonderful children’s shows which not only captivated generations of East Germans – but westerners too.

The kids’ bedtime show Sandman was so beloved on both sides of the border that the West Germans choose to ditch their own capitalist version of the show in favour of the technically superior socialist original – which had the eponymous hero flying to Moscow and Cuba, or driving his Trabant around the landmarks of the people’s republic.

The studios, which celebrate their 100th anniversary next year, are as busy as ever, once-again turning out blockbusters. If you saw Tom Cruise in Valkyrie, Kate Winslet in The Reader, Roman Polanski’s Pianist, Matt Damon’s Bourne Supremacy or Ralph Fiennes in The Constant Gardener then you’ve seen a sample of Babelsburg’s more than 3,000 movies.

Next to the studios is the Filmpark – a cross between a theme park, and museum, where you can explore Babelsburg’s glamourous past, make yourself dizzy in a 4D-action cinema, watch a stunt show, learn how a film is made, create your own TV show, and, of course, meet the iconic Sandman.

True German film buffs can join a walking tour of leafy Neubabelsberg where the stars of the 20s and 30s lived, loved and played. Once again, the ghosts are everywhere. And that sense of cool still pervades the city, from the lively bars of the Altstadt where the beer flows and live music rings out, to the gabled red-brick cafes of the ‘Hollandisches Viertel’ Dutch quarter, built to attract Dutch craftsmen in the 18th century, and which still feels like more like Amsterdam than Central Europe.

In a city surrounded by lakes and forests, you don’t have to go far to escape city life. But for a true back to nature experience, head up to Elstal, where, on a former Soviet army base and tank firing range, a group of nature-lovers have achieved something wondrous.

Having cleared away the mines, shells, dumped live ammunition and wrecked military hardware, the group set up by film cameraman Heinz Sielmann, have re-introduced native species into the pristine wilderness of Döberitzer Heide. They include huge European bison and flighty wild Przewalski horses, as well as the ubiquitous wild boar.

The sight of bison lumbering to their watering hole, while truly wild horses trot around kicking up clouds of dust, is more redolent of the American prairies than the forests of Eastern Germany, but is both exciting and unforgettable – and like so much here, it is only possible because of its intriguing past and enlightened present.