The Queen's lying in state and upcoming funeral will see hundreds of thousands flock to London to pay their respects.
Here's everything you need to know about travelling to and around London during the mourning period.
Lying in state
The Queen will lay in state in Westminster Hall. It will be open to the public from 5pm on September 14 for 24 hours a day until 6.30am on September 19 - the day of the funeral.
There is expected to be long queues with hundreds of thousands predicted to attend. People are not allowed to camp and there will be little chance to sit down.
The queue route is understood to stretch from Victoria Tower Gardens across Lambeth Bridge down to Westminster Bridge, before veering right then left down Belvedere Road, through Jubilee Gardens back to South Bank and along to the Tate.
Train
A spokesman for Greater Anglia said: “The rail industry is doing all it can to ensure people can travel to pay their respects during the period of mourning.
"Where possible, we will be running some extra services and customers should check journey planners for the most up-to-date information.”
Due to Monday being a bank holiday, there will be no time restrictions for using an off-peak ticket.
Coaches
On the day of the funeral there will be major road closures and Victoria Coach Station will be out of use.
All National Express services will be diverted to arrive at Wembley Stadium instead.
Within London, coaches may be diverted or use alternative stops.
Driving
Drivers have been asked to avoid central London if they possibly can due to high levels of traffic and road closures.
Those in cars should allow extra time for journeys and consider alternative routes.
Tube
The Underground is running normally but it may close temporarily at short notice on the busiest days.
Stations expected to be busier include Westminster, Green Park, Charing Cross, Embankment, Victoria, Waterloo, St James's Park, Lancaster Gate, Hyde Park Corner and Marble Arch.
A special service will run on the Elizabeth line railway between London’s Paddington and Abbey Wood on Sunday to ease the pressure on other parts of the transport network.
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