Government guidance, published on Tuesday night, will see the queue follow the path of the River Thames and potentially all the way to Southwark Park.
Tens of thousands are expected to join the queue from Wednesday, while the line will be managed by more than 1,000 volunteers, stewards and police officers.
It promises to be a major logistical challenge for authorities in London as members of the public gather in the capital.
Plans will direct mourners to join the queue on the Albert Embankment, which will run behind the London Eye onto the Southbank before following the river past landmarks such as the National Theatre, the Tate Modern and HMS Belfast, reaching “maximum capacity” at Southwark Park.
Under the arrangements, once mourners have passed through the Albert Embankment they will be directed across Lambeth Bridge and through airport-style security before entering the Palace of Westminster.
The lying-in-state opens to the public at 5pm on Wednesday and will be accessible 24 hours a day until it closes at 6.40am on Monday September 19 – the day of the Queen’s funeral.
Metropolitan Police officers will be joined by volunteers and stewards, while toilets and water fountains will also be provided at various points along the route.
A wristband system will be used to manage the queue, with those waiting in line given a coloured and numbered wristband which organisers said would be specific to each person and “strictly non-transferable”.
Official guidance states: “Your wristband also allows you to leave the queue for a short period to use a toilet or get refreshments, then return to your place in the queue."
St John Ambulance members will be stationed along the route, while more than 100 Scouts will join volunteers from the charity Samaritans to offer help.
Lambeth Palace is also expected to arrange a multi-faith pastor service to provide support to those who need it.
Chief executive of the Scouts, Matt Hyde, called it an “honour” to play a role in proceedings, while Keith Leslie, the chair of the Samaritans, said volunteers would be there to “listen and support anyone who would like to talk openly about how they are feeling”.
The main queue has step-free access, the Government said, with a separate accessible route also planned to run from Tate Britain where timed entry slots will be issued for a queue going along Millbank to the Palace of Westminster.
Guide dogs will be allowed inside Westminster Hall, with sign language interpreters also on hand.
Venues including the Southbank Centre, the National Theatre and Shakespeare’s Globe will open for longer hours to accommodate those queuing, while the British Film Institute on the Southbank will do the same while providing an outdoor screen with archive footage of the Queen.
Chief executive of the Southbank Centre Elaine Bedell said the organisation was “pleased to be able to play our part in providing a little bit of respite”.
Cafes and other businesses are expected to follow suit, while welfare centres will also be in place.
The public are being warned that strict rules on bags will be in place, with those planning to visit Westminster Hall urged to plan ahead.
Once inside, the public can expect to walk past Queen Elizabeth II's coffin, which will be raised on a catafalque and will be draped in the Royal Standard, with the Orb and Sceptre placed on top.
It will be guarded at all hours by units from the Sovereign’s Bodyguard, the Household Division or Yeoman Warders of the Tower of London.
Queues forming to see Queen Elizabeth II lying-in-state in Edinburgh on Tuesday
Jacob King
Queue route to see Queen Elizabeth II lying-in-state
PA Graphics
