Monaco's Prince Albert attends Pierre Casiraghi's bachelor party in Spain

With his wedding just around the corner, Princess Caroline's son Pierre Casiraghi has already gotten the celebrations started. And where would a Monaco royal throw his lavish bachelor party, with guests like uncle Prince Albert? A castle, of course!

According to Spanish newspaper The Vanguardia, Pierre joined his closest buddies to celebrate his last days of singledom at Requesens Castle, a fortress dating back to the ninth century, just north of Barcelona.

Pierre and his fiancée, Italian aristocrat and journalist Beatrice Borromeo, are set to wed on July 25 Photo: Getty Images

For the occasion, the centuries'-old castle transformed itself from a popular tourist spot to host the royal stag party, ahead of Pierre's wedding to Italian journalist and aristocrat Beatrice Borromeo on July 25.

The bachelor party was organized by the groom-to-be's close friend Aldo Comas, who attended school with Pierre at the prestigious Collège Alpin Beau Soleil, one of the oldest private boarding schools in Switzerland. As family friends of the Casiraghi clan, Aldo was also a guest at the spectacular Gstaad wedding of Pierre's brother Andrea Casiraghi and Tatiana Santo Domingo last year.

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Northern Spain's Requesens Castle, which dates back to the ninth century Photo: Requesens Castle

Situated on the peak of a Catalan mountain range, the Requesens Castle was set up with with water and electricity for the royal celebrations, reports the newspaper. The historic building prides itself with picturesque views over which the group toasted to Pierre's future happiness. The evening's menu consisted of traditional local delicacies, including sausages and BBQ meats from the local region of Catalonia, provided by the nearby restaurant La Cantina.

Hotel Can Xiquet where Pierre and his guests reportedly stayed Photo: Hotel Can Xiquet

Some of Pierre's dashing guests arrived on horseback, while the rest made way by car from the four-star boutique Hotel Can Xiquet, where suites cost just around $355 a night.

The nearby castle is a popular destination among locals as well as tourists for its beautiful grounds. The town of Gerona that the castle is situated in is just two hours away from Barcelona and offers a blissful retreat from the hustle and bustle of the city.

The wedding festivities will include a civil ceremony at Monaco's palace and religious vows on one of the bride's family's islands in Italy Photo: Getty Images

Spain is just the first of many locations that will be part of the wedding festivities. Pierre and Beatrice, who have been dating since 2008, will tie the knot in a civil ceremony on July 25 at Prince Albert and Princess Charlene's home, the clifftop Prince's Palace in Monaco. The low-key wedding will be followed by an August 1 religious ceremony on Lake Maggiore in Italy, on one of the Borromean Islands owned by Beatrice's family.

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