Prince Harry is organising a stag do fit for a future King.
His brother William's bachelor party will take place at sea.
Ahead of his April wedding to Kate Middleton, the 28-year-old groom and 20 friends will spend a day enjoying off-shore activities, including speedboat racing and water-skiing.
They will then head off on an evening bar tour – by boat.
According to the Sun, best man Harry has held secret talks with one of the UK's top watersports companies to lay-on the perfect send-off for his brother.
The firm, based on the South Coast, specialises in stag and hen do's.
Their service covers the provision of equipment, such as wakeboards and ringos, and also organising a barbecue.
Alcohol is banned while on the water, but the day will end with a trip up a nearby estuary to visit pubs and restaurants only accessible by boat.
After the bash – expected to cost around £2,500 in total – it is thought the group will spend the night at the country house of a friend.
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