A steam train which carried passengers in the 19th Century has returned to the Tube to mark 150 years since the first London Underground journey.
Ticket holders travelled along part of the original Metropolitan Line - now the Hammersmith & City Line.
They travelled in coaches pulled by an 1898-built steam engine, known as Met Locomotive No 1.
Special events are being held throughout the year to mark the 150-year anniversary of the Underground.
The restored steam engine travelled from its sheds near Earl's Court, west London, to start a journey from Kensington Olympia to Moorgate.
Hundreds of families, rail enthusiasts and interested onlookers took up positions at stations and on bridges to catch a glimpse of the train, as it travelled non-stop.
London Mayor Boris Johnson, who was among passengers on board, said: "It was just extraordinary.
"We had steam coming in through the windows, huge thick clouds of white steam going past and then bits of soot coming through from the engine.
"You understand all those Victorian novels and the assignations that possibly took place on those velvet seats. It was pure Conan Doyle."
London Transport Museum director Sam Mullins said: "We will do more events like this this year and more into the future, here and on other railways."
The first London Underground railway operated on the Metropolitan Railway between Paddington and Farringdon.
Linked to the Met Locomotive No 1 engine was the oldest surviving operational Tube carriage - the Metropolitan Railway Jubilee Carriage 353 - which was built in 1892.
Attached to the Jubilee carriage was a set of four carriages that date back to 1898, on loan from the Bluebell Railway in Sussex.
Known as the Chesham carriages, they began service when the Chesham branch of the Metropolitan Line opened.
Completing the commemorative train was one of the world's oldest electric locomotives in service - No 12 Sarah Siddons.