08/30/2011 at 11:00 AM EDT
Royalty doesn't have to stand on ceremony – or wait for someone to throw them into a swimming pool at a party. They can just jump in for themselves.
, 26, outfitted in matching blue cap, long-sleeved shirt and jeans, was dancing poolside at the Veneranda Club
on Croatia's trendy Hvar island when he lost his balance a bit and took the opportunity to dive right in.
"Harry was dancing around with his arms in the air. He was having a great time and seemed pretty tipsy," the British Sun tabloid
quotes an onlooker as saying. "Suddenly he just jumped into the pool and one of his friends jumped in after him. Everyone thought it was really funny and Harry was laughing his head off. He was soaked to the skin but he didn't care. He loved being the center of attention."
Said another: "Harry's dancing wasn't great. In fact it was embarrassing. But once they realized who he was, everyone wanted to have a photo with him."