Hot Dogs, Folk Dancing and a Zoo: Prince Albert Shares New Details on the Royal Wedding of Nephew Pierre Casiraghi and Italian Heiress Beatrice Borromeo

The Monaco royals don’t generally do small celebrations. (See: Prince Albert’s recent cocktail party for 8,000 marking 10 years on the throne.) But the July 25 wedding of Albert’s nephew Pierre Casiraghi and Italian heiress Beatrice Borromeo will be surprisingly laid-back, the prince tells PEOPLE.

“The wedding service will be in the Palace’s salons, then a garden party – because Pierre and Beatrice want it that way,” Prince Albert, 57, tells PEOPLE exclusively.

The Monaco civil ceremony between Borromeo, 29, and Casiraghi, the 27-year-old son of Albert’s sister Princess Caroline, will be followed one week later by a second religious service on Italy’s Lake Maggiore.

Sources say formal invitations have been sent out from Monaco’s Palace Chamberlain to 700 people for a “simple” summer afternoon celebration that will be “lighter” in tone than the lavish religious ceremony expected to be held on the Borromeo family’s private islands.

Personally involved in the arrangements, Prince Albert is organizing a cavagnëtu for the special day.

“It’s the Monégasque equivalent of a picnic, though we won’t have submarine sandwiches or hamburgers or hot dogs,” he explains.

“Well, maybe hot dogs …” he says with a laugh.

“It’s going to be a summer garden party, a finger-foods-for-lunch thing,” he adds. “With buffet tables and drinks, there’ll be places for guests to sit, but it’s going to be mostly informal.”

For entertainment at the daytime affair, “There’ll be some local folklore dancers. And music. And, we’ll play some pétanque. It’s a light fete and I will give a toast. I’ll try and keep it short and not bore everybody, have them feel I ran on and on.”

Which, he adds, “will be hard because I really like both Pierre and Beatrice.”

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The informal blend of palace and picnic, explains another Casiraghi acquaintance, is Pierre’s expressed wish. “When his father Stefano died, Pierre was only 3, Charlotte, 4. Caroline took all her children away to live quietly in Provence. So Pierre had this [country-style] upbringing, which he loved. He wanted to have a wedding reminiscent of his childhood and to share that with his bride.”

Following the civil ceremony in the palace’s newly refurbished salons, guests will descend to a sheltered terrace known as “the private garden.” Rarely shared with visitors and only occasionally photographed, it’s an area remade by Albert’s mother, Princess Grace, as a center of family activity for her own young children.

“It was an old greenhouse area when she married,” recalls a source familiar with the palace grounds, “and because [Albert’s father Prince] Rainier worked in the palace during summer, Grace decided to convert it, make it more like homes she knew in America where people enjoyed a patio lifestyle.”

“It’s an amazing spot. It’s where they have this 1960s-style swimming pool she had built for the kids to run around and swim. It has a totally Hollywood ambience and feels and looks like an MGM film set.”

Guests will be free to explore the gardens – and the source suggests they will also have access to another shaded area below: the Palace’s zoological garden.

Begun in 1954 as home to Prince Rainier’s considerable private zoo, the terraced 2.2-acre area serves today as a public zoo, animal rescue and display of the family’s collection of birds and monkeys.

More Royals! For everything on William and Kate’s family life and all the sweet christening portraits, pick up this week’s PEOPLE, on newsstands Friday.

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