Trunk route

A trunk road, trunk highway, or strategic road is a major road, usually connecting two or more cities, ports, airports and other places, which is the recommended route for long-distance and freight traffic. Many trunk roads have segregated lanes in a dual carriageway, or are of motorway standard.

In the United Kingdom, trunk roads were first defined for Great Britain in the Trunk Roads Act 1936. Thirty major roads were classed as trunk roads and the minister of transport took direct control of them and the bridges across them. The Trunk Roads Act came into force in England and Wales on 1 April 1937, and in Scotland on 16 May 1937. This development did not extend to Northern Ireland, which has always had a separate system of highway and road traffic law.

At that time, 4,500 miles (7,200 km) of British roads were classified as trunk roads. Additional roads have been "trunked", notably in the Trunk Roads Act 1946. Others, like virtually all British motorways, have entered the system as a result of new construction. As of 2004, Great Britain had 7,845 miles (12,625 km) of trunk roads, of which 2,161 miles (3,478 km) were motorways.

Since 1994, trunk roads in England have been managed by Highways England (formerly the Highways Agency), while Scotland has had responsibility for its own trunk roads since 1998; these are currently managed by Transport Scotland, created in 2006. The Welsh government has had responsibility for trunk roads in Wales since its establishment in 1998.

England has 4,814 miles (7,747 km), Scotland has 1,982 miles (3,190 km) and Wales has 1,048 miles (1,687 km) of trunk roads, inclusive of motorways. Highways England publishes a full network map of trunk roads and motorways in England.

Most interurban trunk roads are "primary routes", the category of roads recommended for long distance and freight transport. Not all primary routes are trunk roads, the difference being that maintenance of trunk roads is paid for by national government bodies rather than the local councils in whose area they lie. Primary routes are identified by their direction signs, which feature white text on a green background with route numbers in yellow. Trunk roads, like other "A" roads, can be either single- or dual-carriageway.

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