Following a procession from Buckingham Palace, Queen Elizabeth II’s coffin arrived at Westminster Hall in central London, where it will lie in state until her funeral.

Prince William and Prince Harry walked alongside King Charles III and other members of the royal family as the coffin made its way down the procession route.

In 1997, the two brothers marched side by side in a funeral procession for their mother, Princess Diana, a moment that both have said had a profound impact on them.

A gun carriage was used to transport the coffin. It was adorned with the Imperial State Crown and a floral wreath, and it was draped in the Royal Standard.

Military personnel surrounded the Queen’s coffin as it was carried down The Mall, Whitehall, Parliament Street, Parliament Square, and New Palace Yard before entering Westminster Hall, where Archbishop of Canterbury Justin Welby conducted a brief service.

Welby told CNN that “playing a part in saying goodbye” to Elizabeth is a “gift.”

The Archbishop told CNN’s Clarissa Ward in the crowd on Wednesday that it is a huge privilege and honor to be a part of the occasion.

According to the royal undertakers Leverton & Sons, the Queen’s coffin was built more than 30 years ago and is made of English oak lined with lead.

It will remain at Westminster Hall, in the heart of the British parliamentary estate, until Monday, when she will be laid to rest.

Members of the public will be able to walk past the coffin, which is on a raised platform known as a catafalque, beginning Wednesday evening. Thousands of people are expected to line the streets of the capital, with some possibly sleeping out overnight to pay their respects.

Harry’s participation in the procession on Wednesday is the latest in a series of appearances with William since the Queen’s death, as the brothers have sought to put on a show of unity despite tensions in recent years since Harry stepped down as a senior royal.

The joint appearance of William and Harry, as well as their wives Catherine, Princess of Wales, and Meghan, Duchess of Sussex, in Windsor on Saturday was unexpected and unannounced. According to CNN, William invited the Sussexes to the walkabout to see the memorials left for the Queen and to greet well-wishers.

On Sunday, the Queen’s coffin was transported from Balmoral Castle, where she died, to Edinburgh. The six-hour journey was part of the late monarch’s eight-day journey to her final resting place.

Mourners waited in line outside St. Giles’ Cathedral in Edinburgh on Monday evening to pay their final respects. According to the Scottish government, over 26,000 people were allowed to file past the Queen.

The Queen’s coffin was transported from St. Giles’ Cathedral in Edinburgh to Buckingham Palace in London on Tuesday.

It was transported in a hearse from the cathedral to Edinburgh airport before being flown to RAF Northolt in west London on board a C-17 Globemaster transport plane.

The coffin was then driven to Buckingham Palace, where it was met by the Queen’s family and left to rest overnight in the Bow Room.