All the best photos of Kate Middleton, Meghan Markle and other royals at RAF centenary service

Members of the royal family gathered at Westminster Abbey to celebrate the Royal Air Force's centenary year on Tuesday. It was the largest gathering of royals since Trooping the Colour, with the Duke and Duchess of Cambridge, Duke and Duchess of Sussex, Prince Charles and Camilla and the Queen among members of the family to attend the service. The service was followed by a Buckingham Palace royal salute and a flypast.

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Although it was originally unknown whether mum-of-three Kate would be attending the event, as she is still on maternity leave from her royal duties after welcoming her baby son, Prince Louis, in April, the royal looked delighted to attend the service with her husband, Prince William, and the pair were spotted laughing and chatting as they took their seats. It is thought that she could attend Wimbledon later this week following the official royal appearance. 

The Duchess of Cornwall, looked beautiful dressed in a white dress with a matching hat adorned with a large bow, while accessorising her look with white heels with a pale pink cap, a white clutch bag and a four-strand pearl necklace. She completed the look for the special service with an RAF brooch pinned to her dress. 

Meghan Markle smiled while entering the Abbey while linking arms with her husband, and accessorised her stunning Dior dress with a black fascinator and cream shoes. Meanwhile, Prince Harry looked handsome in his army uniform, complete with medals, and white gloves. Arriving ahead of Prince Charles, Camilla and the Queen, the service marks the biggest turn out for the royal family since Trooping the Colour in June. 

Princess Anne arrived at the service to mark the centenary of the RAF on Tuesday. The Princess Royal looked to be in good spirits while dressed in a cream and brown ensemble with a matching feathered hat. She completed the look with a brooch to pay tribute to the RAF and their amazing history.

Despite feeling "under the weather" in late June, and missing her great grandson Prince Louis' christening on Monday, the Queen looked to be in great spirits as she made her way inside Westminster Abbey, and smiled as she greeted clergymen upon her arrival. Her Majesty has a busy week ahead of her, as she will be hosting Donald Trump on Friday. 

Dressed to the nines in their army uniforms, Princes William and Harry chatted to one another before entering Westminster Abbey. The two brothers both spent time in the RAF, and both trained as helicopter pilots with the RAF's Search and Rescue Force. Meanwhile, Harry attending the Defence Helicopter Flying School at RAF Shawbury. 

The Queen gave a speech at the event as the RAF's Air Commodore-in-Chief, saying: "Presenting the Royal Air Force with a new Queen's Colour provides an opportunity to congratulate the service for your remarkable contribution to defence over the last 100 years. Tenacity, skill and gallantry have been your hallmarks as you helped safeguard freedom and security in many parts of the world." 

The royal family watched the flypast of more than 100 RAF aircrafts that went across the skies of London in the biggest display of military aircraft in recently memory. In one memorable moment, 22 Typhoon jets spelled out '100' to make the special anniversary. 

The Queen looked delighted to be surrounded by her family while watching the flypast dressed in a royal blue silk coat with a turquoise collar and dress by Angela Kelly, accessorising the look with a diamond star brooch. Speaking about the event, the head of the RAF Air Chief Marshal Sir Stephen Hillier: "It is a tremendous coming together of a whole range of RAF capabilities, and a celebration of the quality of our people, and it is that connection between the Royal Air Force and her Majesty the Queen."

The foursome arrived at Westminster Abbey together, and looked to be in good spirits as they smiled to those lined up to greet them on the way into the Abbey. Meghan and Kate's style differed greatly, with Meghan dressed in a chic black gown with her favoured choice of a boat neckline, while Kate opted for a pale blue number with a matching fascinator.