The carriage made its way at a pace of 70 steps per minute down The Strand, Temple Bar, Fleet Street and Ludgate Hill to St Paul's. The wheels of the 1.5-ton carriage had been changed from steel to rubber so it runs more quietly on the road.
The Band of Her Majesty's Royal Marines Portsmouth led the procession, striking eight bass drum beats to set the pace and playing funeral marches by Beethoven, Mendelssohn and Chopin.
The route was lined by members of all three services in full ceremonial day dress, officers wearing black armbands, with colours draped and rifle muzzles pointed downwards towards the ground as a mark of respect.
More than 4,000 police officers were on duty to ensure security amid heightened fears of a terror attack sparked by the bombing of the Boston marathon in the US.
As the procession moved forward, a gun salute was fired at one-minute intervals. Among the three 105mm light guns operated by the Honourable Artillery Company were two used in the Falklands, which were last fired in anger at Goose Green and the final assault on Port Stanley.
The Queen led mourners at the ceremonial funeral of Baroness Thatcher in St Paul's Cathedral today as thousands lined the streets of London.
Falklands residents say they owe their freedom and their riches to Margaret Thatcher. Today they paused to reflect and to remember.
Baroness Thatcher was honoured with a ceremonial funeral at St Paul's Cathedral in the presence of the Queen and dignitaries.