Four million Londoners cram onto the city's Underground passenger railway nearly every day, but it is a rarer event for Prince Charles.

He rode the British capital's bustling commuter network on Wednesday for the first time since 1986.

The heir to the British throne and his wife Camilla took a one-stop journey from Farringdon to King's Cross on the Metropolitan Line as part of celebrations to mark the 150th anniversary of a transport service affectionately known to Britons as the "tube".

But Britain's Daily Mail reported the prince's tube experience was a little more elite than what it would be for the general public.

"Fortunately for the heir to the throne and his wife, the Duchess of Cornwall, their train was (unusually) clean, running on time - and had been helpfully cleared of other commuters," The Mail reported.

The prince did have some trouble getting through the electronic ticket barrier and had to be shown how to swipe his card. However, his wife was used to the experience from her pre-royal days and got through with no problem at all.

The short journey was a rare enough event to cause some confusion at the prince's press office, which initially said he had last ventured onto the Tube in 1979.

"This is just to let you know that it has come to our attention that The Prince of Wales has travelled on the London Underground more recently than 1979. In 1986 The Prince and Princess of Wales travelled by tube to Heathrow Airport to open Terminal 4," a spokeswoman said in an email to media.

"We're sorry that our previous information was incorrect. Our archives of Royal engagements prior to 1988 are not computerised and in this particular instance a search under 'The Prince of Wales takes the Tube' did not bring up an event which had been logged as the 'official opening of Terminal 4'." 

- Reuters