The Special Roads Act 1949 (12, 13 & 14 Geo. 6. c. 32) is an Act of the Parliament of the United Kingdom that allowed for the construction of roads reserved for special classes of traffic, many later to become known as motorways;^[1] although all motorways are special roads, not all special roads are motorways.^[2]

The Act defined nine classes of traffic:

• Cars, motorcycles and light vans with pneumatic tyres
• Goods vehicles and military vehicles
• Motor vehicles controlled by pedestrians
• Other motor vehicles
• Vehicles drawn by animals
• Vehicles drawn or propelled by pedestrians
• Bicycles
• Animals ridden or led
• Pedestrians

Subsequent legislation added a further two classes:

• Motorcycles under 50cc
• Invalid carriages

The Severn and Wye Bridges, now part of the M48, was one of the first roads to be designated a Special Road.^[2] In 1955 the Ministry of Transport announced the construction of the first two Special Road Schemes, the Lancaster Bypass, and the Preston Bypass.^[3]