Pippa Middleton is beautiful in blue at the Boodles Boxing Ball

Pippa Middleton celebrated completing the Otillo Swimrun World Championships with a night out on the town. The Duchess of Cambridge’s sister looked ravishing in blue at the glitzy Boodles Boxing Ball at London’s Grosvenor House, which benefits The Gordon Ramsay Foundation.

CLICK ON PHOTOS FOR FULL GALLERYpippa middletonPippa Middleton wowed at the Boodles Boxing Ball

Pippa looked sensational in a floor-length halterneck blue gown, with cut-out detailing and embellishment on the front. She accessorised with a pair of silver peep-toe sandals and a glitter box clutch bag. The stylish 32-year-old chose to wear almost no make-up, and channelled old Hollywood by wearing her glossy brunette tresses down in loose waves.

Despite having completed the gruelling swim-run competition in Sweden - which she described as “one of the hardest things” she’s ever done – Pippa showed no signs of tiredness, looking as radiant as ever as she joined stars including Gordon Ramsay and Holly Branson for the glitzy bash.

Read More: 32 times Pippa Middleton wowed us

Competing alongside her younger brother James and her friends James Matthews and Jons Bartholdson, Pippa completed the course in 13 hours, 4 minutes and 24 seconds and came in 82nd.

#otillo15 #pippamiddleton & Jöns Bartholdson finish ÖTILLÖ 2015. Amazing!

A photo posted by ÖTILLÖ Swimrun World Series (@otillorace) on

Pippa Middleton participated in the Otillo Swimrun World Championships

“It’s relentless,” Pippa, who had trained in Sweden especially before the race, told Reuters. “Much of the running is trail running on uneven ground, hopping over rocks on the shore line, dipping in and out of bays.”

The author and columnist went on to describe the challenge as “an unusual and unique event, not for the faint-hearted,” but something that she had wanted to do because she was “taken by the idea of competing in the stunning surroundings” of the Swedish archipelago islands.

The sports enthusiast is no stranger to taking on tough challenges – earlier this summer she completed her first marathon in Kenya in aid of Tusk Trust, the conservation charity supported by her brother-in-law Prince William.

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