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Prince Charles and Duchess Camilla are seen at their home at Clarence House prior to leaving for his 70th birthday bash at Buckingham Palace Thursday night.
Handout, Clarence House via Getty Images

Britain's Prince Charles turned 70 Wednesday and the longest-serving heir to the throne celebrated in style at a glittering Buckingham Palace party hosted by the queen.

Prince William and Prince Harry, Duchess Kate and Duchess Meghan were all spotted arriving at the bash. Their cousins, Princess Beatrice and newlywed Princess Eugenie, were also in attendance, along with her new husband Jack Brooksbank. A contingent of continental royals were also seen heading into the palace.

Both Kate and Meghan sported intricate updos and statement earrings but photographers had to settle for shooting them from outside their cars as they left Kensington Palace to head to the party. Kate's dress appeared to be a one-shouldered pink concoction. Even less info could be gleaned from the photo of Meghan.

The only royal whose dress was on full display was Charles' wife Camilla, who wore a midnight-blue number from Bruce Oldfield.

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Duchess Kate and Duchess Meghan were snapped driving out of Kensington Palace en route to the party at the big house.
Max Mumby/Indigo/Getty Image

The queen toasted her firstborn, a lifelong environmentalist, who revealed he has planted trees for his grandchildren, with a fitting smile.

In remarks shared by the palace, the sovereign declared, "It is a privilege for any mother to be able to propose a toast to her son on his 70th birthday.  It means you have lived long enough to see your child grow up. It is rather like – to use an an analogy I am certain will find favor – planting a tree and being able to watch it grow."

She continued, "Over his 70 years, Philip and I have seen Charles become a champion of conservation and the arts, a great charitable leader – a dedicated and respected heir to the throne to stand comparison with any in history – and a wonderful father."

In a symbol of just how much things have changed in the last 20 years, Queen Elizabeth also gave credit to his second wife, Duchess Camilla, calling her the one who "sustains" him.

The queen did get in one joke, courtesy of the Queen Mother, who died in 2002.

"My mother saw me turn 70, of course," she shared. "And she was heard to observe that 70 is exactly the age when the number of candles on your cake finally exceeds the amount of breath you have to blow them out."

Earlier in the day, Charles made his own joke about the milestone at a tea with other new septugenarians. 

"It's rather like indigestion," he said. " 'Many Happy Returns' are not quite the same as you get older."

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Prince Charles of Wales poses for an official portrait to mark his 70th birthday in the gardens of Clarence House, with Prince George, Duchess Camilla, Princess Charlotte, Duchess Kate, Prince Louis, Prince William, Prince Harry and Duchess Meghan on Sept. 5, 2018, in London.
Clarence House via Getty Images

His birthday week also saw the unveiling of a new family portrait of the Wales clan. The photos by Chris Jackson show Charles with his wife Camilla, sons Prince William and Prince Harry, their wives Duchess Kate and Duchess Meghan and his grandchildren: 5-year-old Prince George, 3-year-old Princess Charlotte and 6-month-old Prince Louis.

There was also a performance of "Happy Birthday" performed in Buckingham Palace's front courtyard by the Welsh Guards Band. 

"We Salute you and thank you for your ceaseless support to @BritishArmy personnel and their families," the British Army in London shared on their Twitter. "Happy Birthday!"

The Prince of Wales also appared on the cover of the latest edition of Country Life, which he guest-edited. He urged readers not to take the natural world for granted but to "think ahead to what our grandchildren will want and need."

Contributing: The Associated Press

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