I first visited Berlin in winter 1990, a year after the momentous events that led to the fall of the German Democratic Republic. I was studying German literature at university and Berlin was a city I had already explored through the pages of novels, such as Döblin's wonderful Berlin Alexanderplatz. When I was there the Wall was still standing, although it was being steadily eroded by souvenir hunters armed with hammers and chisels, each one eager to salvage a concrete piece of Cold War history. I remember how deeply strange it felt, unreal even, to walk beside what the GDR had termed an "Antifaschistischer Schutzwall" (anti-Fascist protective barrier), venturing into areas where not long ago only armed border guards were allowed to walk. More than a hundred people were killed trying to escape to the West from the eastern sector.

Buildings near the eastern side of the Wall looked as though they had been trapped in a time warp, their blackened façades still pock-marked with bullet holes and shrapnel scars from the last war.

The sign at Checkpoint Charlie looked like a prop from a Cold War movie. At any moment, I expected to catch sight of Harry Palmer hurrying past to a rendezvous with a Soviet spy in some dark Berlin alley.

When I went back at the end of the 1990s, Berlin was being transformed. The city had become one giant building site. Potsdamer Platz was a vast, muddy hole in the ground and cranes stalked the city's skyline. The strident sounds of construction - pile-drivers and pneumatic drills - were the birth cries of a new united Berlin.

Revisiting the city today I'm struck by how different it feels. The mud, bulldozers and blackened façades have largely gone. The city's monuments, like the Brandenburg Gate, have now been cleaned and restored. Grime scrubbed away and scars healed. The once divided city has been replaced by an apparently united and confident capital. There are new glass and steel edifices on every street, it seems. As a result the city's past is less visible. But it's still there. And sometimes all you have to do to find it, is to look down at your feet.

Stolpersteine - stumbling stones - commemorate the victims of National Socialism and are placed in the pavement outside their former homes. There are thousands of these Stolpersteine in Berlin's streets. It's a beautifully simple and resonant idea, the brainchild of artist Gunter Demnig. These stumbling stones make the past vividly present: it's there beneath your feet, waiting to be discovered like the layers of history that lie just under the surface of any ancient city.

"Irgenwann fällt jede Mauer" - eventually every wall falls. That was one of the slogans painted onto the Berlin Wall. And, indeed, most of the Wall has now gone, ground up to make gravel for the roads that now link East and West Berlin. A structure that once divided people finally helped to bring them back together again. In today's somewhat sterile Potsdamer Platz, a small piece of the Wall remains, its graffiti-scrawled surface now embellished with pieces of chewing gum. The structure that once defined this city is now almost invisible, an absent presence whose former course is traced through the square by a line of unobtrusive cobblestones. Once again, history lies beneath your feet in this city.

 

Alongside the River Spree, a longer section of the Wall remains, turned into an impromptu canvas for street artists and renamed the East Side Gallery. It includes this great piece by Thierry Noir who, together with Christophe Bouchet, was one of the first artists to paint the western side of the Wall in 1984.

Sadly the future is uncertain for at least part of what is the longest remaining stretch of the Wall. The land beneath it is growing more valuable by the day and developers are gathering for the kill. A new apartment block and a hotel are on the drawing board and once again the bulldozers are on the move.

In the new Berlin there is undoubtedly much that is impressive, such as Norman Foster's reconstruction of the Reichstag. The view across the city from its dome is truly memorable. It was certainly worth getting up early on a bright Sunday morning to see it, before too many tour groups arrived. It's a remarkable structure. But in this city haunted by its past, what particularly struck me was the graffiti made in 1945 by Soviet soldiers, who scratched their names on the parapets of the roof as they looked out across the blackened, bombed-out ruins of a once great city.

A city is a palimpsest. Each generation writes their own urban story. But some traces of the past need to be retained as we hurry into the future.

Daniel Libeskind's Jewish Museum (2001) is another powerful piece of architecture. Instead of the uplifting transparency of Foster's dome, Libeskind's building is full of unsettling, disorientating spaces, such as the Holocaust Tower, where the distant sounds of the city echo in the darkness.

The Holocaust Memorial, designed by Peter Eisenman (2005), was certainly powerful but I found it also strangely anonymous. A grey, nameless necropolis at the heart of the living city. Coming across the Stolpersteine in Berlin's cobbled streets was for me a far more poignant reminder of the city's - and Germany's - dark past.

While I was in Berlin I saw an exhibition at the Pergamon Museum about one of the earliest cities - "Uruk: 5000 Jahre Megacity". If you're visiting Berlin before it ends in September and you're interested in the history of cities, this is a must-see. They have brought together an extraordinarily rich collection of artefacts illustrating the life and culture of the world's first urban civilization.

Like Berlin, Uruk was also famous for its wall, some 9 km long and constructed using 306,000,000 bricks. For the Sumerians who founded Uruk more than five thousand years ago, Eden was not a garden but a city. In their legends the first city was called Eridu and it was created by the god Marduk. He wanted to give his people a place of shelter, a refuge to protect them from a natural world that can be harsh and unforgiving. The Sumerians did not long for some mythic rural idyll, an unobtainable Arcadia. They believed the city was the place where all their dreams would be realised. And Uruk became one of the largest of their cities - although, with respect to the organisers of the exhibition, not quite a "megacity".

The exhibition is superb though. This 4000-year-old clay plaque of a winged goddess (possibly Ishtar) struck me as being especially beautiful.

Berlin has certainly changed since I first visited. That's not surprising. Change is an essential part of urban life. Old structures must make way for new ones. But there is a powerful continuity, too, in cities. That continuity has at its heart the human story of desires and dreams, a story that stretches back to Uruk and beyond. Amidst the glass and steel and optimism of today's cities, we need reminders, like the Stolpersteine, of those human stories.

After a few days in Berlin, I caught the ICE train down south to Munich, where I lived in the early 1990s. It's a beautiful city, but of course very different from Berlin, both then and now. Apart from the Dirndls and Lederhosen, it's always been a more affluent and expensive city. For foreigners like me, the dialect is also far more difficult to understand. One of my first ports of call in Munich was the Olydorf, or the 1972 Olympic Village, where I used to live.

It's been renovated recently which I hope means that today's student occupants no longer have to put up with cockroaches in the apartments and pigeons occupying the balconies. (Eventually I became quite skilled at dispatching cockroaches with a rolled up copy of the Süddeutsche Zeitung.) Some things do change - and for the better.

But I was relieved to see that other things hadn't changed. My favourite café-bar in Munich was Drugstore, opposite Wedekindplatz in Schwabing. It was founded in the swinging sixties and is still going strong. It's the friendliest bar anywhere. And they serve great food. What more can you ask for? Well, perhaps another beer...

In fact, in Munich many things were just as I remembered them. The Englischer Garten, which opened in 1791, is still one of the most beautiful urban parks I know.

The Viktualienmarkt still offers a mouth-watering selection of the most perfect food on the planet.

And, of course, a Weizen remains the best beer on this world or any other.

But some things have changed in Munich. The city is expanding, as is clear from the extended U-Bahn lines. The city's art galleries have been attracting international visitors since 1830 when the Glyptothek opened. New galleries have opened since I was there, including the Pinakothek der Moderne and the beautifully designed Museum Brandhorst. The Lenbachhaus, one of my favourite art galleries (I love its Blaue Reiter collection), has also been expanded and is now even better than before.

If you go to the Lenbachhaus, don't miss Rudolf Schlichter's brilliant portrait of Bertolt Brecht. Although in most people's minds, Brecht is associated with Berlin - both before and after the war (he is buried in the Dorotheen Cemetery in what was East Berlin) - he was born and grew up in Augsburg, not far from Munich. He also lived in Munich in the 1920s.

Walking around Munich today and travelling on its excellent public transport system, I was pleased to see that the city that used to pride itself on being the "Weltstadt mit Herz" - the world city with heart - is now far more diverse than it once was. The world has come to Munich. Despite its conservatism and love of tradition, Munich is now truly a global city.

It was great to revisit Berlin and Munich. They are very different cities. But both are dynamic, exciting places with long histories and promising futures - cities where anything can happen. A sign I saw in the wonderful Prenzlauer Berg district of Berlin put it perfectly: If you can dream it, you can do it.

And that's true now in vibrant cities like Berlin or Munich, just as it once was in Uruk.

You can see all the photos in this post, as well as more from Berlin and Munich, on my Flickr page in higher quality than my site allows (there's a set for Berlin and Munich). I hope this post and the images encourage you to visit some of the places for yourself.

If you do, here are a few recommendations of cafés and restaurants.

In Berlin: Restoration 1900, a great local bar-restaurant in Prenzlauer Berg. For a special occasion Alpenstueck is worth trying. The Friday Turkish market off Kottbusser Strasse is amazing. If you're looking for fresh food, this is the place to go. Near here at Paul-Lincke-Ufer 42, Cau is a friendly bar with a wonderfully sunny terrace beside the canal. If you're in Mitte, Café Oliv is worth a visit.

In Munich: wie schon gesagt, Drugstore. One of my other favourite bar-restaurants is Atzinger near the university - a relaxed place, that serves huge portions and great beer. If you're around Frauenhoferstrasse, Das Kranz is a great little restaurant. For superb Vietnamese food look no further than Cyclo in Theresienstrasse. And for a delicious vegetarian menu, go to Prinz Myshkin not far from Marienplatz. If you like beer gardens, head for the Chinesischer Turm in the Englischer Garten. An amazing setting to enjoy a beer. Viel Spass!