Many people tend to walk at about 1.42 metres per second (5.1 km/h; 3.2 mph; 4.7 ft/s).
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In urban design
The typical walking speed of 1.4 metres per second (5.0 km/h; 3.1 mph; 4.6 ft/s) is recommended by design guides including the Design Manual for Roads and Bridges. Transport for London recommend 1.33 metres per second (4.8 km/h; 3.0 mph; 4.4 ft/s) in the PTAL methodology.
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https://en.wikipedia.org/wiki/Preferred_walking_speed