London's red Routemaster double-decker buses – as much a symbol of the British capital as Tower Bridge or Big Ben – are going the way of the empire.

The last of the buses went out of regular service on Friday after a final trip of the 159 route on Oxford Street.

Famed for their hop-on, hop-off rear platforms, they failed to meet modern standards of safety and accessibility.

Crowds gather at a bus stop to board the last routemaster double-decker bus as it travels along Oxford Street in central London, Friday Dec. 9. (AP Photo/Lefteris Pitarakis)

But they won't disappear completely – not in a city with a huge tourist trade.

Two "heritage routes" will be retained: No. 15 from Trafalgar Square to Tower Hill via Fleet Street and No. 9 from the Royal Albert Hall to Aldwych via Knightsbridge and Piccadilly.

The double-decker Routemaster was introduced in the 1950s, the last bus designed specifically for London. With its light aluminum construction, it was a model of efficiency, carrying more passengers than most modern buses.

Its replacements will include boxier modern double-deckers and articulated "bendy buses."

Fred Martin, 59, who turned out for the last regular trip, told the BBC: "I grew up with the Routemaster when I was living in Enfield in north London. We are losing so much of our tradition."