When it opened at 5 p.m. on Friday, the queue of visitors stretched for almost three miles along the River Thames, according to an official tracker.
Prince William and Prince Harry joined King Charles III and other members of the royal family in walking behind the coffin as it made its way along the procession route.
The two brothers also marched side by side in a funeral procession for their mother, Princess Diana, in 1997, a moment which both have said affected them deeply.
The coffin was carried on a gun carriage. It was adorned with the Imperial State Crown next to a wreath of flowers, and covered with the Royal Standard.
Military personnel surrounded the Queen’s coffin, which was carried along The Mall, Whitehall, Parliament Street, Parliament Square and New Palace Yard, before entering Westminster Hall, where a short service was conducted by the Archbishop of Canterbury Justin Welby.
Welby told CNN that it is a “gift” to “play a part in saying goodbye” to Elizabeth.
Speaking to CNN’s Clarissa Ward on Wednesday in the crowd, the Archbishop said that it is a huge privilege and honor to be part of the occasion.
The Queen’s coffin was constructed more than 30 years ago, and is made from English oak lined with lead, the royal undertakers Leverton & Sons told the British newspaper The Times.
It will remain at Westminster Hall, in the heart of the British parliamentary estate, until her funeral on Monday.
From Wednesday evening, members of the public will be able to file past the coffin, which rests on a raised platform or catafalque. Thousands are expected to queue along the streets of the capital, with some potentially sleeping out overnight in a bid to pay their respects.
A joint appearance of William and Harry and their wives Catherine, Princess of Wales and Meghan, Duchess of Sussex in Windsor on Saturday came as a surprise and was not announced in advance. William invited the Sussexes to the walkabout to see memorials left for the Queen and greet well-wishers, a source told CNN.
The Queen’s coffin was transported from Balmoral Castle, where she died, to Edinburgh on Sunday. The six-hour route marked the first leg of the late monarch’s eight-day journey to her final resting place.
Mourners queued outside St. Giles’ Cathedral in Edinburgh on Monday evening for their turn to pay their final respects. The Scottish government said more than 26,000 people got to file past the Queen.
On Tuesday, the Queen’s coffin was transported from St. Giles’ Cathedral in Edinburgh to Buckingham Palace, London.
It was taken from the cathedral to Edinburgh airport in a hearse before being flown to RAF Northolt airbase in west London on board a C-17 Globemaster transport plane.
The coffin was then driven to Buckingham Palace, where it was received by the Queen’s family and then left to rest in the Bow Room overnight.
