A74 road

A74
Glasgow—Carlisle Road
Click map to enlarge
The former A74, now B7076, with the Caledonian Railway crossing overhead via the Harthope Viaduct, on the West Coast Main Line in Dumfries and Galloway. One half of the former dual carriageway has been removed.
Route information
Length:	93 mi (150 km)
History:	Constructed 1825 Classified as A74 1923 Replaced by M6 and A74(M) and M74 motorways
Location
Counties:	Cumbria, Dumfries and Galloway, South Lanarkshire, City of Glasgow
Primary destinations:	Carlisle, Gretna Green, Lockerbie, Crawford, Hamilton, Cambuslang, Glasgow
Road network
Roads in the United Kingdom Motorways A and B road zones

The A74, also known historically as the Glasgow to Carlisle Road, was a major road in the United Kingdom, linking Glasgow in Scotland to Carlisle in the North West of England, passing through Clydesdale, Annandale and the Southern Uplands. A road in this area has existed since Roman Britain, and it was considered one of the most important roads in Scotland, being used as a regular mail service route.

The road received a substantial upgrade in the early 19th century under the direction of Thomas Telford, who made significant engineering improvements, including a new route over the and the Metal Bridge just in England just south of the border. Engineering improvements continued throughout the century and into the 20th, and it became one of the first trunk roads in Britain in 1936.

From the 1960s the road started to be replaced by a parallel motorway. The last remaining section of all-purpose road on Telford's original alignment, the so-called "Cumberland Gap" between Carlisle and Metal Bridge, was replaced by a motorway in 2008 after years of delays due to a breakdown in discussions between the English and Scottish parliaments.

The road was infamous for its allegedly high accident rate, being dubbed a "killer road", which exacerbated the need to provide an alternative motorway route. Several high-profile accidents occurred, most notoriously the debris of Pan Am Flight 103 in December 1988, which partially fell on the road near Lockerbie and caused several fatalities.

Today the A74 is a short link road in Glasgow that does not run on any of Telford's route and, as the A74(M), a portion of the replacement motorway.