Darius Sanai follows Europe's longest river from its tiny source in southern Germany to the Black Sea
So, was that it then? Brown rivulets were emerging from the grass, converging into a little brook. The source of the great river Danube, it appeared, was a muddy field.

I stood by a gate in the drizzle, accompanied by a Friesian cow, staring at it to try and find some existential significance. I found none. I retired to my gasthof, where I bought some home-made Danube Source Schnapps. It was a small flat bottle with angular shoulders, the type you sneak into maths classes at school. I kept it, in case things became more harrowing later on.

The next morning over black bread and ham I met a fit young blond couple who said they were cycling the length of the river. "You'll get to the end before me, then," I said. They freewheeled off down the country lane at 10am. Another 1,479 miles to go, all downhill.

I was travelling by foot, bus, train, and anything else I came across. I'd decided to travel the length of the Danube because I was young, bored with my job and too cowardly to go down the Amazon. The Danube, after all, was nearby. It was supposed to be romantic and it was also Europe's longest river, if you didn't count the Russian waterways. It went through nine countries, from a field in southern Germany to the edge of the former Soviet Union on the Black Sea (which seemed cheekily defiant, given that everyone else in those days was going the other way).

My next stop was Austria. Linz, to be precise, the place where, according to William Shirer's The Rise and Fall of the Third Reich, the young Adolf Hitler spent his childhood wandering the riverbanks plotting world domination.

The river had no such effect on me. For fun I told the tourist office I was a writer and they provided me with a beautiful, Slissom, poetic brunette called Waltraud as a guide. We spent a sunny afternoon drinking most, very strong cider, on a farmhouse terrace on a hilltop with a view across to the white peaks of the Alps. Would she care to have dinner with me one day? I thought she said "yes". But when I rang the next day, her husband answered the phone. The answer was "no". I ate at a bierkeller in town, washing down kaisekrainer, white veal sausages, with peach schnapps.

In Vienna, the first city en route, I arranged to meet an old acquaintance in Havelka, one of the city's historic coffee houses. We had last met on the day the Berlin Wall came down, two excited youths watching history being made. Now, five years later, she seemed old and weary as she poured out her worries, over thick coffee and a Sachertorte. Still only 23, she had been married and was now divorcing.

How sad. It rained on Vienna for three days. The Danube, skirting the edge of the city, beside a row of tower blocks, was grey-black. I imagined it as a Central European Volga running through some Soviet industrial zone on the steppes. And yet this was still western Europe.

Crossing the line of the old Iron Curtain was like stepping back 20 years, but the weather improved and people were slower and friendlier. In Komrno, Slovakia, I stayed in a hotel where five liveried waiters served me fried pork, chips, rice and beans for 75p. I was the only guest and, for five days, the only customer in the dining- room. Between my visits, the waiters would lean on the bar, still in waistcoats and bow ties, smoking strong cigarettes.

On Friday night I went to the nightclub underneath the town's main bar. It was packed with gorgeous girls and moody-looking boys but I couldn't understand a word anyone said. I bought people beers at 20p a go and we toasted in English, Slovak and Hungarian. The next day I walked off my hangover by the riverside: rows of rusting, disused cranes stood by empty docks overlooking a river of green and red effluent.

Further east, I began to turn slightly deranged, as I tired of trying to communicate in pidgin English and German. When I passed the halfway point of the river's course on a passenger-ferry by a forested hillside in Hungary, I had a celebratory beer and let out a cheer. The other passengers moved away.

In Budapest I treated myself to a three-star hotel with luxuries such as hot water and a concierge. He recommended I visit the Blues Bar, which turned out to be a strip joint. Inside, I was charged pounds 100 - all the money I had - for a vodka. I was accompanied to the nearest cashpoint by a huge Magyar waiter.

In desperation I went to the casino in the Hilton and bet the remainder on roulette, and won back pounds 50. Then an elderly couple on the train south from Budapest insisted I stay with them in Pecs. The city was near the Croatian border, enclosed in lovely green hills and surrounded by vineyards. I stayed in their little, cramped flat for two days, sleeping in the room of a long-lost absent son.

By the Croatian border, I stayed with German-speaking wine farmers living in a German-speaking village. They were a hearty, hard-working couple who ate lunch at precisely 11.30am before returning to the white grapes in their vineyards. They said they were descended from Donauschwaben, Germans from the province of Swabia who had migrated 1,000 miles down the river during a German Reich hundreds of years ago. They had German books, a German flag in the kitchen and sold wines to Germany. They had never been there.

The river flowed on but politics intervened. It was the end of Serbia's war in Croatia and the start of hostilities in Bosnia. The Yugoslav authorities refused me entry on suspicion of being a journalist. A sultry torpor was gathering over the Balkans. I had to take a train through Romania, finally rejoining the river beside a gorge on the Serbian-Bulgarian border.

Of Bulgaria, I had my own prior image, of drinking red wine in hayfields by the river's edge with friendly peasant women. Instead I stayed in a little industrial town, a depressed inland port called Vidin. The docks were closed because of sanctions against Yugoslavia. The local rock band, which played near-perfect Beatles covers in an outdoor cafe, gave me a room in their tower-block flat. It was decorated with carpets and tapestries like an old farmhouse. Every evening they would grill lamb kebabs and wave the smoke out of the window.

By this stage, almost 1,240 miles down the river, more of my two-month journey had been by train or bus than by boat. This was partly because there weren't many passenger-boats going down the river. It was also because I was too lazy and cowardly to persuade barge captains that they had to take me on board and not rob or kill me.

But finally, here in the river's delta, stretching along the Black Sea coast of Romania and Moldova, there were no roads and no railways. The passenger-ferry from Tulcea, the last town on the railway line, set off down one of a maze of waterways, separated by reeds. Flamingoes swooped up and dropped all around in great clouds of pink. We stopped at a collection of muddy houses on the riverbank and a few people climbed on board, carrying children, melons, a pig and a fridge.

At Crisan, the ferry stopped. This was the end of the river and the end of my journey was very close. A cart- horse was being loaded up by the docks and a family were piling belongings into a fishing boat. There was no sound of the 20th century. A fisherman sold me a green bottle filled with home-made vodka, which I put in my bag next to the schnapps from the source. I walked two miles to the sea, which was brilliant white with the setting sun.