Royals Gone Wild! Monaco Wedding 'By Far One of the Most Fun Ever,' Guest Tells PEOPLE

When Pierre Casiraghi and Beatrice Borromeo wed – for the second time – in a religious ceremony in Italy, it was an elegant affair befitting a royal couple. But the real fun unspooled at the parties that followed. And it wasn’t as prim-and-proper as you might think!

“This was by far one of the most fun weddings I have ever attended,” a guest tells PEOPLE of the royal union of Casiraghi, 27, currently 7th in line of Monaco’s succession, and Italian heiress Borromeo, 29, a journalist.

With an impressive guest list that included Crown Princess Mette-Marit of Norway, the groom’s mother, Princess Caroline and his aunt, Princess Stephanie. “There may have been a number of reigning monarchs and the crème de la crème of the continent s high society, but it was an eclectic mix of parties, events and entertainment,” says the attendee, who was a guest at both the civil ceremony in Monaco on July 25 and the religious ceremony on Italy’s Borromean Islands (yes, they belong to the bride’s aristocratic family) on Aug. 1.

The lavish festivities, says the attendee, “ranged from a modern picnic in Monaco to medieval fighting and sword swinging – complete with appropriately adorned horses – at the Rocca [di Angera]” on the evening of the civil ceremony. (The “Rocca,” which stands on a lakeside hilltop in the town of Angera, is also called Borromeo Castle!)

“After the religious ceremony, we were given the afternoon off to relax and prepare for the evening celebrations,” the guest continues. “We were sailed from the coast of the lake, where our hotel was located, to the Rocca for the evening celebrations on an antique steam boat.”

The bride and groom arrived about an hour later, “and at a certain point in the evening we were all invited to gather on one of the terraced walls of the fortress,” says the guest. “There below us we were surprised by a 100 or so people dressed in medieval costumes, which together with horses re-enacted a medieval tournament. There were tents, armors, swords and spears galore. There was also music played with traditional instruments to match the atmosphere.”

And at one point, even the groom got in on the action!

“He was brandishing a sword, playfully anointing as knights of his ‘kingdom’ all his friends that were standing close to him, much to the amusement of everyone.”

The historical theme was not just for fun, however.

We were told the medieval atmosphere was meant to recall the important history of the fortress and some of the main events that took place in the venue in those times,” reveals the guest. “The fortress still has richly frescoed ceilings in certain halls and some rooms are just as they were in the 1300s.

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Another time-traveling twist? A traditional medieval market re-created inside the fortress courtyard brimming with colorful flowers and fruit.

After the sword-fighting show, the couple danced for hours with their friends and family to a mix of music ranging from DJ David Guetta s hits like “Dangerous” to more classic songs.

“The rosé Champagne was flowing and many of the guests indulged,” says the attendee. “It is one of the bride’s favorite drinks.”

The day after, the celebrations continued with a pool party at the Grand Hotel for some 40 or so of the younger guests.

As the alcohol flowed, a couple of late arrivers were punished for showing up late by being thrown (fully dressed) by the groom’s buddies into the pool. At one point there was even a diving competition, with Pierre competing and Beatrice serving as a poolside judge, calling out the points she was assigning to each dive.

And her newlywed outfit said it all.

“Beatrice wore a short bright yellow sleeveless dress,” says the guest, “but the cutest thing was her pochette, made of brown leather with ‘Mrs. Casiraghi’ written in big letters on the front.”

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