When the new district of Mareterra officially opens in Monaco at the beginning of December, the most expensive real estate in the world will come firmly into view. Here, in condominiums and villa designed by the crème de la crème of architects, including Renzo Piano, Tadao Ando and Lord Norman Foster, the price per square metre has reached values that make Hong Kong look relatable. If the Special Administrative Region tops out around the €50,000 mark, Mareterra can more than double that.
“To be honest,” says Alexander Kraft, chair and chief executive of Sotheby’s International Realty, France and Monaco, who is based in Monte Carlo, “it can go up to €120,000 a square metre.” All properties have already been sold.
To put this into perspective, the principality of Monaco is 1.98 sq km — a sliver of land slotted between the Mediterranean Sea and the mountains. Its tiny size goes back to 1861, when 95 per cent of its land was ceded to France in exchange for its independence. The Grimaldi family has ruled it as a separate state ever since. Now, its exclusivity and emphasis on security — along with its zero collection of income tax or capital gains — makes it the desired location for the super-rich.
“When I arrived here 20 years ago, it was stuck in the 1980s,” says Kraft. “It was sleepy and old-fashioned. Now a number of new buildings have brought better amenities — spas, gyms, restaurants. The university has expanded, specialising in luxury; the local schools are top notch. But it’s still a big village.”
Mareterra adds an extra 6 hectares, or 3 per cent, of land, and includes 110 apartments, four town houses and 10 mystery-shrouded villas. Half of it is new public realm and its 500m promenade is one of the rare spots in Monaco where you can be right by the sea. The site has been planted with nearly 1,000 trees, including pines and oaks, and a typical Provençal maquis at ground level. There are the requisite ponds, paths and bridges. It has cost in the region of €2bn.
“It is our first national eco-district,” Prince Albert II of Monaco tells me from his lofty palace on Monte Carlo’s rocky promontory. “It embodies our era’s call for a renewed harmony between humanity and nature. It is a project that reflects Monaco’s enduring promise to safeguard the Mediterranean’s unique beauty and biodiversity while addressing the needs of a modern, sustainable principality.”
By eco-district, the Prince means that the project conforms to the standards of Haute Qualité Environnementale, the French designation for sustainable development. This applies not only to the land construction (of which more later) but its ongoing operation. There are 9,000 sq m of solar panels across the site; heat pumps will power all heating and cooling mechanisms; rainwater capture will irrigate plants and trees. But the needs to which he refers are presumably less ecological. Increasing Monaco’s real estate is essential to its financial success.
Depending on your tastes, Monaco — with its policemen on every corner and low crime rate, Nobu restaurants and Louis Vuitton stores, its own royal family — might be lifestyle nirvana. All the more so if your preferred neighbours are tennis players, footballers and racing drivers. This is not a country of chin-stroking intellectuals, but a place to put your money.
“It might hurt (to buy here),” says Kraft, “But property has gone up 30-40 per cent in the past 10 years. Certain locations by 50 per cent.” In 2023, the number of sales fell by about a fifth year-on-year at 418, according to Knight Frank — there are just 21,123 homes in the principality — but so far this year both transactions and prices have returned to slight growth, according to both Knight Frank and Savills. Savills research also shows that new-build sales have accounted for a higher proportion of the total over the past couple of years: they are now more than 30 per cent, compared with a historic average of about 10 per cent.
From the 1920s onwards, Monaco has expanded its borders by building in the only direction it can: into the sea. The biggest of these developments, Fontvieille, was created in the 1970s, and added 23 hectares. Another piece of land, the beachfront Larvotto, was magicked into existence in the 1960s just below avenue Princesse Grace. In 2021, it was brought up to date with a promenade designed by Renzo Piano and a Mexican restaurant called Sexy Tacos.
“The first time I came to see the Prince, it was in 2010, for a small museum that never happened,” says Piano, the charismatic Italian architect, now 87, from Genoa, where his company RPBW (Renzo Piano Building Workshop) is based. “Then a few years later, his nephew Andrea Casiraghi called us about Mareterra.”
Piano says he looks out at the same sea as the Grimaldis, who originally hail from Genoa, and besides, it’s only a 45-minute helicopter ride away. (Piano and the Prince both have helipads on their roofs.) “We have a light lunch and we talk about the fragility of the planet,” says Piano of his royal meetings.
The Prince wanted a Piano building and he wanted it to be called Le Renzo. Now it stands next to the sea like a massive liner in dry dock, its two parts seeming to float above the new land that is paved in silvery-grey limestone from a quarry at Châteauneuf-les-Martigues near Marseille.
“It is raised five metres above the ground (on supporting columns) and you see right through the under section to the water,” says Piano of the bipartite design. “Like it is flying.” In its transparent undercroft will be shops and restaurants. One, called Marlow, will offer casual British dining. Le Renzo is 62m high and 125m long, but it wears its might surprisingly lightly.
The building contains 50 apartments, including a penthouse quadruplex. None is smaller than 400 sq m. “We want people to live here with their families,” says Guy Thomas Levy-Soussan, the 52-year-old Monégasque who showed me around the site in late September. He will not disclose how many families have bought, but I am told that half of purchases have come from existing residents and the other half from new buyers outside Monaco.
The views from the apartments are spectacular — the city rising up the hill in one direction, and the sense of being far out to sea in the other. “When you buy in Monaco, there is no right to the view, certainly not of the sea. You cannot claim it anywhere,” says Levy-Soussan, of the inevitability of something being built in front of your apartment block. But here at Le Renzo, there’s a good chance nothing will get in the way.
Levy-Soussan is the chief administrator of the SAM L’Anse du Portier, the company established by the principality to run this project. “My mother was born in the palace, she became the private secretary to Princess Grace,” says the former investment banker and wine importer, who wears a string of perfectly turned ebony beads around his wrist. “My grandfather was like the major-domo. Princess Grace was my godmother.” He could hardly be better placed to carry out the wishes of the royal family.
Now he lives “on the top of the hill, right next to Monte Carlo”, but takes me round the new land with pride. “The prince wanted Mareterra to feel like a natural addition,” he explains, as we walk towards a newly sculpted hill that allows the freshly minted landscape to seamlessly rise up to the existing city.
“We say this is the smallest museum in the world,” laughs Levy-Soussan, as we enter an outdoor space enclosed on three sides, where a sculpture by the 20th-century artist Alexander Calder, more than 5 metres high, stands in a pool of still, dark water. The piece, called “Quatre Lances”, had been in storage for a number of years. “The palace had the idea to reinstall it here. It’s a place to be quiet, to be calm. You can sit here, and look straight out at the Mediterranean. If you were to continue walking up the new hill and then the old, you would come to 19th-century Monte Carlo and the pastel Belle Époque building that is the Monte Carlo casino. It wouldn’t take you long. Nothing in Monte Carlo is ever more than 10 minutes away.”
Mareterra’s urban plan was developed by the Paris-based architects Valode & Pistre. More than 40 per cent is green. The landscape was completed by Michel Desvigne, who teaches at Harvard and whose previous projects include the Greenwich Millennial Park in London and the Old Port of Marseille. “The idea was to allow the maximum amount of vegetation,” says Denis Valode. “It brings quality to the project, but also a sense of place.” Indeed, in the largely mineral environment of Monaco, Mareterra already feels quite an oasis.
Before that, however, the land had to be made. In 2018 a dredging operation cleared away sediment down to a natural rock ledge at a depth of 50m. On this, a stone embankment was constructed to carry a system of caissons, or huge concrete boxes. This created a belt that was filled with sand. Earlier still, local fishermen, from Monaco to Toulon, were invited over a two-month period to lift the bass from around the site, to be relocated further down the coast. A 500 sq m patch of Posidonia, a marine plant with nitrogen fixation capabilities, was moved and replanted nearby. A vulnerable coral reef needed to be protected from possible damage.
Scientific experts were in supervision, including those from Andromède Océanologie, who were in charge of the relocation of the Posidonia, and several environmental surveys to ensure that the project either respected or enhanced the marine environment. The caissons, with their uneven concrete surfaces, have been constructed to provide a new home for marine wildlife. Whether that makes this project unimpeachable, time will tell.
But no expense has been spared. The developers say that to build the land cost £1bn. Another £1bn was spent on construction (with further expenses covered from profits of sales). The Mareterra project was leveraged entirely by investment from nine families, all of whom have residency here. They include Monégasques — Briantis, Casiraghis and Pastors — as well as the Kazakh Bulat Utemuratov. Pastor is also the developer, the company now run by the infamously hard-balling second-generation Patrice Pastor, who has brought this immense project in ahead of time.
“During Covid, we never closed. That was very important,” says Levy-Soussan. “We were lucky because all the work was happening outside. We brought food on site, and we managed to keep everyone apart.” (In neighbouring France, extreme rules made it almost impossible to leave the house unless for essential work or medical reasons.) On the day I visit, there are still thousands of workers strewn across every part of the six hectares.
There is much talk at Mareterra of Monaco as a place for families — “not like in the 1970s”, says Levy-Soussan, referring to the reputation it garnered back then as a magnet for gamblers. This is echoed by Ianis Ennaji, a senior private banker at Barclays Private Bank Monaco, who describes the principality as a rather different kind of hotspot these days. “The demand for large family homes has been on the rise,” he says.
This is driven in part by a new requirement, that a family applying for residency must now have a property big enough to accommodate all its members. Meanwhile, to enhance Mareterra’s local feel, Denis Valode says: “We included a little port with just 16 berths because that’s characteristic of any Mediterranean town. And it’s only for smaller boats, up to 16m.”
The principality still struggles in its promotion of a squeaky-clean image nonetheless. In spite of a number of measures introduced to reverse its ingrained reputation as “a sunny place for shady people” (as W Somerset Maugham once described the wider Riviera region), in June 2024 it was placed on the Financial Action Task Force’s so-called “grey list”, which aims to combat money laundering and the financing of terrorism. It is hoping to remove itself by January 2026, with the introduction of heightened self-scrutiny.
Equally, it’s hard to get beneath the surface here. Take the mystery surrounding Mareterra’s monolithic villas. I am prevented from seeing them, though they are the jewel in Mareterra’s crown, and forbidden to talk to one of the chosen architects. (Valode & Pistre originally designed all 10. But you can’t force an architect on an UHNW.) Each has 0.2 hectare of land, and from 1,500 sq m to 2,000 sq m internally. At Kraft’s calculations, that means they are worth up to €240mn.
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“We are protective about the villas,” says Levy-Soussan, though presumably he means the identity of their buyers. “And for someone to acquire one, we have to make sure that they take the time to come here and present themselves.” Something a company cannot do. “It’s for security.” Internal protection is one thing; global reputation, another.
Reached by an underground road, with subterranean parking, the villas are exceptional pools of invisibility and discretion in the midst of this overbuilt country.
As for who will occupy them, who knows? I have been told that one owner is already planning on renting theirs out. Another reportedly asked for his living quarters to be on the lower floors, as he would hardly ever be there and the staff might as well enjoy the view.
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