The service, which will take place on Sept. 16, will mark the first royal funeral of its kind in modern history

Katharine, Duchess of Kent stands on the balcony of Buckingham Palace during the annual Trooping the Colour Ceremony at Buckingham Palace on June 16, 2012 in London, England. The Westminster Cathedral or the Metropolitan Cathedral of the Precious Blood of Our Lord Jesus Christ, in London, UK.

Katharine, Duchess of Kent (left); Westminster Cathedral.Credit : Indigo/Getty; Nicolas Economou/NurPhoto via Getty

Official details about the funeral for Katharine, the Duchess of Kent, have been released by Buckingham Palace.

The Catholic service will take place at Westminster Cathedral, in London, on Tuesday, Sept. 16, at 2 p.m. local time, per a release from the palace. The Duchess’ coffin will rest in the private chapel in Kensington Palace ahead of its arrival at Westminster.

The coffin will arrive at the cathedral the day before the funeral on Monday, Sept. 15, where the Rite of Reception and Vespers will take place the evening prior to the Requiem Mass.

King Charles and Queen Camilla, along with other members of the royal family, “will join The Duke of Kent and members of The Duchess’ family” for the Sept. 16 service. The coffin will then be taken by hearse to the Royal Burial Ground at Frogmore in Windsor.

“Flags will be half-masted at all official Royal Residences flying the Union flag on the day of the Funeral,” the statement continued.

Katharine, Duchess of Kent, attends the wedding of James Ogilvy and Julia Rawlinson at St. Mary The Virgin Church on July 30, 1988 in Saffron Walden, England.

Katharine, the Duchess of Kent, in 1988.Georges De Keerle/Getty

Katharine’s service will mark the first royal funeral at Westminster Cathedral since its construction in 1903, and will be the first royal Catholic funeral in modern history. It was Katharine’s wish to have her funeral at the cathedral, and the plans have the support of the royal family.

The guest list for the funeral includes members of the royal family, the Duchess’ family, friends and representatives from her charities and regimental affiliations. The service will be private and will not be broadcast.

Katharine, who died on Sept. 4 at the age of 92, was married to Queen Elizabeth’s cousin, Prince Edward. They had three children: George, Earl of St. Andrews, Lady Helen Windsor and Lord Nicholas Windsor. (Katharine was also open about experiencing a miscarriage as well as giving birth to a stillborn son).

Prince Edward, Duke of Kent and his new bride, Katharine (nee Worsley) after their wedding at York Minster on 8th June 1961

Prince Edward and Katharine after their wedding in 1961.Popperfoto via Getty

The Duchess broke from royal tradition when she converted to Catholicism in 1994. She became the first member of the British royal family to become part of the Roman Catholic Church since 1685, per the Irish Times.

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At the time, Katharine reportedly found comfort in the Catholic church while reeling from mental and physical health challenges, according to the BBC.

Katharine, Duchess of Kent attends a pre-wedding gala dinner on the eve of the Royal Wedding of Prince William to Catherine Middleton at the Mandarin Oriental Hyde Park on April 28, 2011 in London, England.

Katharine in 2011.Max Mumby/Indigo/Getty

“I do love guidelines and the Catholic Church offers you guidelines,” she said, per The Mirror. “I have always wanted that in my life. I like to know what’s expected of me. I like being told, ‘You shall go to church on Sunday and if you don’t you’re in for it!’ “

Queen Elizabeth approved of the conversion, and the Duke and Duchess of Kent were permitted to keep their titles and succession place despite the Act of Settlement 1701, which stated only protestants could succeed in the royal family.

Katharine stepped away from public life in 1996 in order to teach music. In 2002, she took another step back from the royal family and discontinued use of “Her Royal Highness” title, though she continued to attend family events.