"We'll be down among the crowd," the royal tells PEOPLE of his plans for this weekend's 10th anniversary celebration

Credit: Eric Gaillard/Reuters/Landov

Monaco’s Prince Albert is poised to celebrate 10 years on the throne – and he’s also capping his busiest year yet.

As he prepares for a super-sized celebration in his honor this weekend, the royal, 57, is reflecting on the year that saw the arrival of his twins with wife Princess Charlene, the babies’ grand double christening, a major palace remodeling and globe-circling travels for environmental causes.

Asked about his highlights from the past decade, the ruler of the world’s second-smallest country tells PEOPLE in an exclusive interview, “The happiest moments of the last 10 years would of course be the wedding with Charlene, then the birth of the twins. That has to be the top of any list.

“Then, of course, meeting the people of Monaco, getting to know the Monégasques, and also the travels I’ve been fortunate to take for my foundation, the Red Cross and for humanitarian work,” he continues. “Travels to Asia and Africa to see what help we’re able to bring to kids there, where we’ve built villages. Places we’ve been able to make a difference.

“And another ‘happiest’ moment,” says the Amherst College graduate with a smile, “I’m thinking will be this weekend. A little get-together, a garden party for 7,000 to 8,000.”

The weekend celebration commemorating Albert’s reign includes an open-air cocktail party hosted by Albert and Charlene, 37. It’s a casual style that stands in stark contrast to the formality that marked the era of his late parents, Prince Rainier and Princess Grace.

When asked if there will be a big balcony moment this weekend like that of another royal family, he replies with an emphatic no.

“There won’t be a crowded balcony,” he says. “In fact, there won’t be any balcony at all. We’ll be down among the crowd.”

When PEOPLE remarks that the Grimaldi family’s 700-year reign over Monaco is much to celebrate – along with a growing line of succession – Albert playfully corrects the math. “That’s 718 years, thank you. And, yes, it’s wonderful to see the next generation coming up, going through their big steps in life. To see my nieces and nephews getting married, having kids. It’s a great satisfaction.”

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On July 25 he will host a wedding reception for nephew Pierre Casiraghi and his Italian heiress bride, Beatrice Borromeo.

“There’ll be finger foods and activities and I’ll give a toast,” he teases. “But try to keep it short and not bore everybody. But it will be hard because I really like both Pierre and Beatrice.”

Then in August, both he and Charlene plan a vacation away from royal activities. “The last time we had a private dinner alone was May 31. That’s why we need a vacation!”

The couple have already begun talking “pretty loosely” about their children’s future, educating them from an early age concerning their royal roles. “We will continue talking about it,” he says. “The passage of time with children is very quick and it should be as enjoyable as possible.

“It’s already been seven months since the birth of Jacques and Gabriella – even longer with my other two children [from previous relationships] – and I haven’t always had the time to be with the children as much as I’d like.”

As for the next decade of his reign, “My hopes for the 10 years ahead? That’s a pretty big agenda,” he says.

“I hope that we’re able to continue to do good work for Monaco. The quality of life is good here, but we’ve more actions to take towards sustainable solutions for our generation and our children’s generation.”

As the sovereign ruler of a country whose reputation and influence vastly outweigh its physical size, Albert is in a unique position – and he is quietly recruiting other royals to the cause of environmental action.

With a shared passion for environmental causes, he says he feels closest to Britain’s Prince Charles – and enjoys regular contact with the royal houses of Sweden, Spain, Belgium and England.

“I probably speak most to Prince Charles, because he’s spoken out about environmental issues. [Norway’s Crown Prince] Haakon as well and Dutch Prince Willem Alexander, though he’s more about water issues. We’ve meet about Arctic concerns,” says Albert, who holds the distinction of being the only living head of state to have trekked to the North Pole.

“The others are as worried about environmental and ecological issues. We talk about how we can join forces on certain concerns as leaders seeking a common front. We think it can be extremely valuable to people.”

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