For a vast, overwhelming expanse of urban density, it's tough to beat Tokyo's reputation. The city's centuries-old tradition of privately owned, small-plot real estate has guaranteed a jumble of close quarters while encouraging seemingly endless sprawl.

Roppongi Hills, a $4 billion, mixed-use development that opened in 2003 in the city's central Minato-ku district, counters all those notions. For starters, half of the 28.7-acre hillside site is open space with touches such as whimsical, artist-designed benches.

The project is the culmination of nearly a half-century of effort by Mori Building Corp. A family outfit founded in 1959, the company is changing Tokyo's skyline, street-scape, and lifestyle by assembling small holdings to create larger projects, many of them in the 7.85 square miles of Minato-ku. It is the nation's largest private redevelopment effort.

The project encapsulates the belief of Minoru Mori, CEO and president of Mori Building Corp., that the only way to make Tokyo more livable is to build upward for living and working while freeing ground-level space for parks and the attractions that transform urban living from depressing to delightful. An additional plus: shortening brutal two- to three-hour commutes by bringing people back into the urban center.

HIGH STYLE: Roppongi Hills, a mixed-use development by Mori Building Corp., is helping to redefine downtown Tokyo as a place to live as well as to work. Overhead pedestrian walkways and underground passages to subway stops help preserve green space at ground level.
HIGH STYLE: Roppongi Hills, a mixed-use development by Mori Building Corp., is helping to redefine downtown Tokyo as a place to live as well as to work. Overhead pedestrian walkways and underground passages to subway stops help preserve green space at ground level.

Richard Rosan, president of the Urban Land Institute, which recognized Roppongi Hills in 2004 as an Award for Excellence finalist in the contest for Asia, says Mori “makes a great point” when he argues strongly for building upward. “He believes it is the only way for Tokyo to survive. ... While Tokyo is an enormous city, almost nobody lives downtown.”

In Minato-ku, home to several other Mori mixed-use projects, there were 159,400 residents in 2000 and 813,000 jobs in 2000 and 2001, making it the third most imbalanced of Tokyo's 23 inner “ku” areas. (Chiyoda-ku, the most out-of-whack district, has 36,000 residents and 888,000 jobs.) Rosan contrasts Tokyo with New York City, where there's a similarly large population, but it is much more evenly interspersed with business.

The Roppongi Hills project took off in 1986 when the Tokyo metropolitan government designated the multilevel target neighborhood a priority redevelopment district. That's when Mori began negotiations with hundreds of small landholders.

Critics—and there are many—argue that by making a horizontal city vertical, its character will inevitably change. Still, Mori moved forward on Roppongi Hills and other nearby projects, such as Atago Green Hills, with 354 units on a site with two 42-story towers centered around a Buddhist temple, and Moto-Azabu Hills, a 222-unit tower that features an on-site kindergarten.

Japan's economy was in a slump in 2003 when Roppongi Hills opened. Yet 85 percent of its 800 apartments were rented. Within a year, they were fully occupied by the target market of singles and couples, in a 50-50 mix of Japanese and expatriates, according to Michiho Kishi, a company spokesperson.

Approximately 2,000 people live in Roppongi Hills in four buildings that range from six stories to 43 stories. They are near—but designed to feel very separate from—a 54-story, commercial-use skyscraper, which houses a bustling art museum and a meeting center for more than 500 people, and the surrounding city-within-a-city, which has a nine-screen multiplex, more than 200 stores and restaurants, a hotel and convention center, a covered outdoor performance area, and a tea garden. Richard Doone of London's Conran & Partners headed the team that designed the apartment buildings. They distinguished the residential buildings from the office tower by using natural materials that would develop patinas as they aged.

The project includes its own green, natural gas–powered, electric co-generator system that can provide 72-hour backup during a blackout and a rooftop garden with rice paddies that help stabilize buildings during an earthquake (the landscaped mass acts as a pendulum that works against building oscillation during a quake). There's a branch post office, banks, and an almost 30-foot-high bronze spider that has become an iconic landmark and meeting place. The place hums with activity, a popular local destination woven into the larger megalopolis by direct connections to existing highways, local roads, and four subway lines.

Beth Hughes is a freelance writer based in San Francisco.

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