Prince Harry's very unusual birthday party plans revealed ahead of landmark birthday

Prince Harry is set to celebrate his 40th birthday this Sunday in Montecito, surrounded by loved ones. But the Duke of Sussex has a unique afterparty planned for himself and his mates.

According to Express.co.uk, Prince Harry has arranged a trip to the Californian mountains near his residence with a select group of his best friends.

The soon-to-be 40-year-old plans to conquer the Montecito peak, part of the Cold Spring Trail in California , just a stone's throw from the mansion he shares with Meghan and their two children, Prince Archie, 5, and Princess Lilibet, 3.

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"The Cold Spring Trail is filled with streams and pools where people often take a swim," a source revealed. "But they'll also have to deal with snakes and other wildlife, like large cats. Harry and his pals will get a real taste of the wilderness as they embark on one of the lengthy hikes. Let's hope he's bringing an experienced guide along," reports the Express .

As he approaches his 40th birthday, insiders close to the Duke say he's looking forward to the future, keen to continue the work he loves most - from furthering the success of the Invictus Games to promoting The Archewell Foundation globally . This year, as part of the Sussexes' multi-year partnership, Prince Harry also announced an exciting new non-fiction series with Netflix .

The series, primarily filmed at the US Open Polo Championship in Wellington, Florida , and The USPA National Polo Centre, is a collaboration with Boardwalk Pictures. It promises to give viewers an exclusive peek behind the curtain of professional polo's elite world.

Meanwhile, Prince Harry and Meghan are reportedly planning their third foreign tour for this year. Africa is the likely destination, with Botswana and Lesotho being considered - locations where Prince Harry's charity Sentebale operates.

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The Duke and Duchess of Sussex have been well-received during their tours of Nigeria in May and Colombia last month. Prince Harry is also preparing for a solo trip to New York later this month to "advance a number of his patronages and philanthropic initiatives".

His visit coincides with the UN General Assembly High-level Week and Climate Week, which runs from September 22 until September 29. He is also expected to attend a Diana Award event in honor of his late mother.

The Sussexes have been contacted for comment.

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