10 Most Expensive Streets in the World: Billionaire’s Row

The Aga Khan turned the Costa Smerelda, Sardinia, into his holiday retreat in the 1960s, and billionaires have played there ever since. The region's most sought-after road, the winding Romazzino Hill, first made headlines after Italian industrialist Carlo de Benedetti sold his seafront Villa Rocky Ram for $149 million to a Russian buyer. Savills recently sold a two-bedroom apartment measuring approximately 656 square feet for an asking price $6.8 million on this street. Exclusive hotels located here include the Cala di Volpe and the Romazzino, both part of The Luxury Collection. A historical owner of this area is Saudi Arabian politician Ahmed Zaki Yamani.

6. Chemin de Ruth, Geneva

Average price per square meter: $37,000

Price change year on year: -5%

Chemin de Ruth is located in the heart of Switzerland's Cologny, close to the shores of Lake Geneva. The mansions on this stone-walled street come with more land than most other streets of Cologny, often with landscaped gardens and large swimming pools. Many properties overlook the lake, with views of the famous Jet d'Eau, the United Nations buildings and the headquarters of the World Economic Forum. The record price for a house on this street is $36 million. "There are a few very significant residences that are slowly being introduced to the market in a discreet manner," said Knight Frank's Bailey. "This is keeping the prices so high."

5. Paterson Hill, Singapore

Average price per square meter: $42,500

Price change year on year: +6.5%

The cul-de-sac Paterson Hill is widely considered the city-state's "Billionaire's Row." Prices here have jumped in the last year, largely because of currency fluctuations. Paterson Hill is located in the prestigious district 09, a residential area within close proximity to the Orchard Road Shopping Belt with its collection of designer boutiques and Michelin-starred restaurants. Various international schools are nearby. The most expensive condominium on this road is The Marq. In November 2011, it achieved a record price of $5,509 per square foot for a 3,003 square foot unit.

4. Boulevard du Général de Gaulle, Cap Ferrat, France

Average price per square meter: $79,000

Price change year on year: -5%

The highly exclusive peninsula of Cap Ferrat may be the most sought-after piece of land along the Mediterranean Côte d'Azur, resulting in its being the world's priciest non-urban location. Situated about nine miles from Monaco, the Cap has long attracted folks such as Brad Pitt and Angelina Jolie, Paul Allen and, in an earlier era, Charlie Chaplin. The Boulevard du Général de Gaulle loops around the peninsula, spotted with beachfront villas and luxury hotels, including the famous Grand-Hôtel du Cap-Ferrat. Rarely transacted waterfront properties with panoramic views over the Mediterranean tend to command the highest prices.

3. Avenue Princesse Grace, Monaco

Average price per square meter: $86,000

Price change year on year: +5%

Monaco, host to the F1 Grand Prix and the annual Monaco Boat Show, is a melting pot for Europe's super-rich. The principality's exclusive Avenue Princesse Grace winds along the sea front. At the peak of the property boom, prices on the street surpassed $135,000 per square meter. Since the recession, values have cooled to an average $88,000 per square meter, although Knight Frank believes they're on their way up again. Because of finite space, most developments on the avenue are now rental only, so recent constructions, such as the Mirabeau and number 21 Avenue Princesse Grace, command a premium. Knight Frank says many of these constructions are being bought off-plan as both an investment and a lifestyle option, as Monaco seeks to establish itself as a family destination.

2. Kensington Palace Gardens, London

Average price per square meter: $107,000

Price change year on year: +2%

Properties on the world's second most-expensive street change hands for as much as $195 million. The arrival of the Duke and Duchess of Cambridge at Kensington Palace has no doubt helped boost prices. This private, tree-lined avenue is home to the French, Russian and Japanese embassies, and some of the world's most famous billionaires. Indian-born steel tycoon Lakshmi Mittal owns number 9a and 18–19. His next-door neighbor at number 17 is Russian billionaire Roman Abramovich, owner of the Chelsea Football Club.

1. Pollock's Path, The Peak, Hong Kong

Average price per square meter: $120,000

Price change year on year: +10%

Pollock's Path, which overlooks Hong Kong Island and Victoria Harbor, is the world's most expensive street. The Peak has long been the stomping ground of Hong Kong's super-rich. Prices on neighboring Severn Road and Barker Road rival those of Pollock's Path, chic new developments on this winding path have pushed up prices. For example, Skyhigh, developed by Hong Kong movie star Stephen Chow at number 10–18 Pollock's Path, set a record in 2011 when apartment number 10 sold for $103 million. That same year, the former French Consulate at 8 Pollock's Path sold for $75 million.

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