In an urban setting, a skyway, catwalk, skybridge, or skywalk is a type of pedway consisting of an enclosed or covered bridge between two or more buildings. This protects pedestrians from the weather. These skyways are usually owned by businesses, and are therefore not public spaces (compare with sidewalk). However, in Asia, such as Bangkok's skywalks, they are built and owned separately by the city government, connecting between privately run rail stations or other transport with their own footbridges, and run many kilometers. Skyways usually connect on the first few floors above the ground-level floor, though they are sometimes much higher, as in Petronas Towers, SWFC, and Kingdom Centre. A notable exception in North America are the Saint Paul skyways, which are publicly owned, unlike most skyways in North America. The space in the buildings connected by skyways is often devoted to retail business, so areas around the skyway may operate as a shopping mall. Non-commercial areas with closely associated buildings, such as university campuses, can often have skyways and/or tunnels connecting buildings.
The world's largest discontinuous skyway network – Calgary, Alberta's "+15 Walkway" system – has a total length of 18 km (11 mi). The Minneapolis Skyway System is the world's largest continuous system and spans 8 miles (13 km) connecting 69 blocks in downtown Minneapolis.
Other cities in the Midwest, such as Saint Paul, Des Moines, Cedar Rapids, Rochester, and Duluth also have significant skyway systems. On a smaller scale, terminals of large airports are often connected by skywalk systems, as at Manchester Airport, United Kingdom.
The Mumbai Skywalk Project is a discontinuous system of 50 skywalks planned in the Mumbai Metropolitan Region, each 1 to 2 km in length. When completed, the system will be the largest skyway system in the world. The first of these is a 1.3 km (0.8 mi) long skywalk connecting the suburban regions of Bandra and Kurla.
Some cities have the equivalent of a skyway underground, and many locales have mixed subway/skyway systems; see underground city.(Wikipedia)