Speed limit
Videos
Speed limits on road traffic, as used in most countries, set the legal maximum speed at which vehicles may travel on a given stretch of road. Speed limits are generally indicated on a traffic sign ref
A road sign shows maximum and minimum speed limit for different types of vehicle on expressway in China. Speed limit signs are shown in kilometres per hour.
Historic New Hampshire speed limit sign
In 1920 a pastor was fined US$10 (equivalent to $346 in 2025) for "overspeeding his machine ... at a rate greater than 25 mph (40 km/h) ... in what appeared to be a reckless manner."
Example variable speed limit sign in the United States, in mph
Road speed limits in the United Kingdom are used to define the maximum legal speed for vehicles using public roads in the UK.
Speed limit
…Locomotive Acts (in 1861, 1865 and 1878) created the first numeric speed limits for mechanically propelled vehicles in the UK; the 1861 Act introduced a UK speed limit of 10 mph (16 km/h) on open roads in town, which was reduced to 2 mph (3 km/h) in towns and 4 mph (6 km/h) in rural areas by the 1865 "Red Flag Act…
Speed limit sign on a single-carriageway road indicating a speed limit of 50 mph (80 km/h). The limits are posted on both sides of the road.
NSL sign on a single-track road implying a speed limit of 60 mph (96 km/h) or 50 mph (80 km/h) depending on vehicle type
Road sign used to mark the start of a 20 mph (32 km/h) zone
50 mph (80 km/h) sign on a dual-carriageway road