Almost 60 years ago Southampton was at the centre of intense international interest after it was used as an escape route for two of the most notorious spies in British history.

Guy Francis de Moncy Burgess and Donald Duart Maclean had for many years worked at the heart of Whitehall, dealing every day with highly sensitive matters of government foreign policy.

As far back as January 1949, the security authorities had received a report that Foreign Office information had been leaked to what was then the Soviet Union. Investigations narrowed the possible source of the leak to two people, and by May 1951 Maclean was the prime suspect.

The evidence was not strong enough for Maclean to be arrested, but it was agreed at the highest level that he should be questioned.

By then it was too late; a departmental decision had already been taken to give Maclean the chance to resign, although he had survived earlier inquiries into his unsatisfactory conduct and drunkenness.

Maclean was given a long weekend to think about his future, but as soon as he left his office, he contacted Guy Burgess, who had just been recalled from Washington DC following his unsatisfactory conduct, including reckless driving and leaving secret papers unattended.

The two men met in a Soho cafe and took the decision to flee the country. Their avenue of escape using Southampton had already been planned – the previous day Burgess had booked a two-berth cabin on the British Rail ship Falaise, a well-known vessel in the port, which was making an excursion to St Malo in France, via the Channel islands.

The ship was due to leave Southampton at midnight on Friday, May 25. After spending the evening at Maclean’s home in Kent, the two fugitives left, saying they were going to visit a friend in Andover.

In fact they drove in a rental car to Southampton, and left the vehicle at Andrews Garage in the docks.

Later, the Daily Echo reported that the two men were in such a hurry that they “literally threw the ignition key at the attendant’’ and ran off towards the ship.

Next morning, Falaise arrived at St Malo, and the two men went ashore.

They got a taxi to Rennes and there boarded the Paris express, arriving in the capital at 5.40pm and most likely going straight to the Soviet Embassy.

In a few hours they were on their way to Moscow via Prague on an Aeroflot flight.

For a while, the disappearance of the two diplomats was a mystery and it wasn’t until 1955 that the British Foreign Office admitted both men were suspected of being foreign agents. They had been recruited as Soviet spies while studying at Cambridge University.

In 1952, Maclean’s wife and three children settled in Geneva, Switzerland but she was later to vanish, apparently joining her husband in Moscow.

Finally, journalists based in Moscow were summoned to a hotel where Burgess and Maclean handed over a statement saying they had come to the Soviet Union to work for “better understanding’’ between the Russians and the West. Both denied ever having been spies.

A warrant for their arrest was issued in 1962, 11 years after their initial disappearance. Early in the following year, the “third man’’, Kim Philby, who had tipped off Burgess and Maclean in 1951, followed them into the Soviet Union.

Burgess was by this time a lonely and homesick alcoholic. He died at the age of 52 in a Moscow hospital in September 1963, from heart disease.

Maclean was given the rank of colonel in the KGB. He died in March, 1983, aged 69.