More underground walks

Many cities around the world offer underground or skyway systems that insulate visitors from the harsh elements: heat, cold, pollution, honking cars. Here are five enclosed mini-metropolises to explore.

Montreal: The Underground City network (called RESO in French) has about 20 miles of underground passageways that link metro stations, theaters, museums, universities, hotels, thousands of boutiques and restaurants, and such major attractions as the Bell Centre. Info: Montreal Tourism, 877-266-5687, www.tourisme-montreal.org

Minneapolis: The city's windowed skyways let in natural light but banish the cold. The walkways are above street level, so you have a nice view of those bundled below. The seven-mile network covers 72 blocks and links to downtown hotels, restaurants, shops, theaters, performing arts venues and more. One drawback: Some of the bridges close after business hours or on weekends. Meet Minneapolis, 612-767-8000, www.minneapolis.org Houston: In Houston's Tunnel, travel high or low, but never in the suffocating Texas heat. The seven-mile system contains concourses 20 feet below downtown as well as skywalks with access to hotels, banks, restaurants and various performing arts venues in the Theater District. Shops and services line the walkways, including boutiques, snack bars. The Tunnel is open only during weekday business hours, though a portion can be accessed on weekends. Greater Houston Convention and Visitors Bureau, 713-437-5200, www.visithoustontexas.com

Osaka: In this Japanese city known for shopping, you can spend countless yen — and hours — in sprawling underground shopping arcades centered on subway stations. In addition to thousands of stores, bars and restaurants, there are also art displays, themed streets (Casual Street, Fashionable Street, etc.) and waterfalls. Osaka Convention and Tourism Bureau, www.tourism.city.osaka.jp/en

Singapore: The Southeast Asian metropolis has high humidity and heavy rains, but pedestrians can keep dry and frizz-free in underground passageways that link many buildings around downtown. The biggest subterranean area is CityLink Mall, which has 60,000 square feet of retail and restaurants and connects the City Hall MRT Station to the Suntec Convention Center, five hotels, a movie theater and another mall.

Singapore Tourism Board, 212-302-4861, www.visitsingapore.com

The Washington Post