JOHN SIMPSON

It's a nice city, and nowadays increasingly prosperous, but no one could deny that it's a bit sleepy. That's part of its attraction. You can't imagine how sinister it could sometimes be 20 years ago.

I wanted to go back to Bratislava because of something I recently bought from a man who deals in signed documents. It didn't look very impressive: just an official pink card acknowledging the receipt of a letter. There was a date, 22 February 1988, an address, 'Misikova 49, Bratislavaa, CSSR', a squiggle of a signature from the recipient, and the recipient's name written beside it: Alexander Dubcek.

Yet the signature wasn't the main reason I had splashed out the enormous sum of £8 on the pink card. It was the address I wanted it for.

In a world where people seem to know increasingly little about even the recent past, I should probably remind you who Dubcek was. He was a Communist Party apparatchik in Czechoslovakia, who in January 1968 became the country's political boss. During the Prague Spring, freedoms of all kinds grew and spread, until by August the old Soviet bosses decided it had to stop. They and their allies invaded Czechoslovakia, and Dubcek was flown to Moscow in chains.

But he survived, and ended up under house arrest in his home city, Bratislava. At number 49 Misikova Street. It was there, 23 years ago, that I set out to visit him. I was banned from visiting communist Czechoslovakia, because a couple of years earlier I had gone to Prague and secretly interviewed all the leading dissidents. I was arrested more than once, and slung out of the country. One day, maybe, I'll describe in High Life how, to get their revenge, the Czechoslovak secret police set a trap for me, using a beautiful young woman.

In the summer of 1985, a new boat service started up on the Danube. You could take a day-trip from Vienna to Bratislava, without needing a visa, or even showing your passport: something altogether new for a police state like Czechoslovakia. We would have about three hours in Bratislava: time enough to drop in on Alexander Dubcek.

He had given interviews to the Western press, but after that his phone was cut off. His friends in the West were pretty sure, though, that he would want to speak to us.

So one hot, sunny day in July, a BBC cameraman and I found ourselves on a rather nicely appointed boat. The cameraman took a little tourist movie camera: nothing that would attract attention. Even so, a British couple spotted us. 'I thought we could have a quiet afternoon without bloody Simpson being here,' the man said. I sympathised, but by speaking so loudly he didn't make life easier for us. There were three men in dark suits wandering around the deck, looking the passengers over.

We reached Bratislava and used our map to find Misikova Street, turning back on ourselves several times in case we were being followed. It wasn't hard to find. Number 49 was a pleasant, not particularly large house with a nice straggling garden.

But this isn't a story of amazing journalistic derring-do. When we knocked on the front door, there was no reply. Eventually a woman appeared and told us that Dubcek had been given permission to go and visit his son. If she realised who we were, she was kind enough not to ring the security police.

We hurried back to the river port. To the cameraman's annoyance, I insisted on stopping to buy a fujara, a superb Slovak wind instrument as long as an anti-tank weapon, which makes a haunting sound like an Aboriginal didgeridoo. After all, I said, we're supposed to be tourists.

Dubcek remained a prisoner for four more years. Then, one night in November 1989, when the Soviet empire collapsed and the Czechs and Slovaks freed themselves from a nasty dictatorship without firing a shot or even breaking a window, I found myself in a fourth-storey room overlooking Wenceslas Square in Prague. The room was filled with TV reporters and cameramen, because Alexander Dubcek was about to make his first appearance in public since the Soviet invasion of 1968.

When one of the journalists did something, which annoyed the organisers, they ordered the entire press to clear out. Sadly, my cameraman and I started to leave. Then someone - I think it was the future foreign minister, Jiri Dienstbier, but the room was full of former dissidents who were about to be ministers, so it's hard to be certain - grabbed my arm and said angrily, as though I was being particularly stupid, 'Not the BBC.'

Which is why, 15 minutes later, I was there to see Alexander Dubcek, old and frail but still as sharp as ever, being ushered gently into the room. His arm was held as gently as an elderly father's by Václav Havel, the playwright who had spent years in jail but was soon to be his country's president. He took Dubcek over to the big open windows and helped him onto the balcony overlooking Wenceslas Square, where a million people were waiting to see him. I've seen a lot of wonderful things, but not many of them have been as superb as that moment, when the crowd exploded with happiness. And as he spoke, breaking the silence of 21 years, his speech had them in tears. Me too, I'm not ashamed to say.

When it was over, Havel guided him past me again, and I was allowed to shake his hand. It had been a long wait since the day I went to see him in Bratislava at the address on my official German post office form, only to discover he'd gone out for the day. But, I promise you, it was thoroughly worth it.

John Simpson is the BBC's world affairs editor and can be seen around the globe on the BBC World news channel. BBC World is available in 200 countries and territories worldwide and on selected flights.