Glasgow to Stirling
The M80 is the primary road link between Glasgow and central Scotland. Almost 25 miles long, it was constructed in three stages between 1972 and 2011. It has its origins in the Clyde Valley Regional Plan, published in 1949.
The motorway was formed from an upgrade of the A80 trunk road, much of which was constructed in the 1950s and 60s. It has a mix of urban and rural stretches and features sections of dual two and three lane carriageways. A key section of the motorway network, it interchanges with the M8, M73, M876 and M9.
Improvements to the Glasgow to Stirling road were first proposed in the Clyde Valley Regional Plan of 1949. By the mid-1950s, approval was given to dual the A80 north of Stepps, and for the construction of new bypasses at Cumbernauld and Denny. This work was completed by 1964.
In Glasgow, much of the A80 remained a busy urban single carriageway. The city's highway plan, published in 1965, detailed plans for a 'Stirling Motorway '. This followed a path to the north west of the existing road, terminating on the A80 east of Stepps. The Greater Glasgow Transportation Study, published in 1967, extended the proposed motorway northwards in a line through the Kelvin Valley, linking with the A80 at Haggs.
Progress on the urban section of the Stirling Motorway, also known as the Stepps Bypass, was slow. Initially earmarked for construction by 1980, the project stalled due to local government reorganisation and reductions in funding. Public engagement exercises were undertaken in 1972 and a detailed design published shortly after.
By the 1980s, congestion on the A80 saw the scheme brought forward, although Strathclyde Regional Council altered the original design. These changes necessitated the construction of a large railway bridge south of Barmulloch. Designed by British Rail in Glasgow and based on a bridge over the M60 at Brinnington, it was constructed as part of an advance contract. Eight further advance contracts were undertaken before the main works commenced in November 1989. Designed in-house by Strathclyde's roads team, the £22.5 million project was built by Tarmac Construction. It was opened to traffic on the 8th June 1992.
At the northern end of the project, allowance was made for a future northward extension.
M80 Construction Summary
Having committed several million pounds to the dualling of the A80 north of Stepps in the 1960s, the Scottish Office initially considered the Stepps to Haggs section of M80 a low priority. As peak time congestion began to affect the route it became clear improvements were needed.
Studies comparing the 'off-line' Kelvin Valley route with an 'on-line' upgrade of the existing A80 were undertaken during the 1980s. By the early 1990s, it appeared likely that the offline motorway with three lanes in each direction would be taken forward. This caused some upset locally, particularly due to its proximity to the Antonine Wall at Croy, although others, including the local MP and North Lanarkshire Council were in favour.
In early 1997, it was announced that the 'on-line' option would be taken forward. This was confirmed in November 1999, following the new Scottish Executive's 'Strategic Roads Review'.
Final proposals were published in 2003 on completion of the Central Scotland Corridor Study. Three construction projects were planned: a bypass of Moodiesburn, Mollinsburn to Auchenkilns and Auchenkilns to Haggs.
In the 1960s, difficult ground conditions led to the construction of an at-grade roundabout at the junction of the A80 and A73 at Auchenkilns, north west of Cumbernauld. This had become a congestion hotspot at peak times.
In advance of the motorway upgrade, the Scottish Executive fast-tracked a scheme to construct a grade-separated junction. This was completed in 2005 at a cost of £25 million. It was designed by Tony Gee and Partners and built by AWG Construction Services.
In 2005, it was announced that the motorway upgrade would be taken forward as a single construction contract. The Scottish Executive also confirmed that much of the new road would be constructed as dual two lane motorway, ignoring the recommendations of its engineering consultant.
In January 2009, a £320 million design, build, finance and operate contract was awarded to HMG (Scotland) Ltd, a group consisting of Bilfinger Berger, Northstone and Grahams. The project was completed in the autumn of 2011.
North of Haggs, the motorway is comprised of two sections. The Denny Bypass, between Banknock and Ingleston, originally constructed as a all-purpose dual carriageway, was upgraded to include hard shoulders. This work, which also saw the construction of an additional running lane between Haggs and Bankhead, was undertaken in 1973 and 74 by Balfour Beatty.
The second section, from Ingleston to the M9 at Bannockburn, was also constructed by Balfour Beatty. This new stretch of road, located west of the existing A872, was completed as part of Stage 2 of the £12 million Stirling Bypass. The main designer was Stirling County Council and an official opening was held on 22nd May 1974.
Junctions on the M80 are numbered from south to north, from the M8 at J1 (Provan) to the M9 at J9 (Bannockburn). The motorway is constructed to urban standards with a 50mph speed limit as far as Junction 2 (Robroyston), and takes on rural characteristics thereafter.
Most of the route has dual two lane carriageways with hard shoulders, although two short sections of three lane motorway exist between Junctions 4 (Mollinsburn) and 4A (Low Wood), and Junctions 7 (Haggs) and 8 (Bankhead). A climbing lane is provided on the southbound carriageway between Junction 6 (Old Inns) and 6A (Castlecary).
The M80 is connected to the M8 motorway via west facing slip roads. This fork type junction provides free flow movements for traffic heading to or from the west. Traffic heading to or from the east makes use of surface street connections to the M8 at Junction 13.
The motorway passes below the Glasgow to Coatbridge railway, Royston Road and Robroyston Road before reaching Junction 2. This section, completed in 1992, features Glasgow type sign gantries.
Between Junctions 2 and 4 the road passes through open countryside. At Junction 3 (Hornshill), connection is made with the A806, Kirkintilloch Link Road, completed 2011. Junctions 2, 3 and 4 are full access, allowing for connections to the motorway in all directions.
The M80 interchanges with the M73 at Junction 4 via east facing slip roads. These act as free flow links for traffic travelling to or from the north and south. The motorway temporarily increases in width to three lanes, returning to dual two lanes at Junction 4A.
Limited access to the motorway is provided at Junction 4A, where only south facing slip roads were constructed. South of here the motorway is connected to Traffic Scotland’s network of overhead sign gantries, although variable message signs and CCTV cameras are place along the entire length of the route.
At Junction 5 (Auchenkilns), the M80 interchanges with the A73 dual carriageway, a former trunk road constructed as part of the development of Cumbernauld. This junction, which is a full access 'dumbbell' type, was constructed in 2005, ahead of the main motorway contract.
The motorway climbs steeply between Junctions 5 and 6, acting as a boundary between the newer and older parts of Cumbernauld new town. At Junction 6, a service area is signed, though there is no direct access from the main carriageways. The site is currently operated by Shell. Much of this stretch is affected by peak time congestion, in line with predictions made when it was decided to remove a third traffic lane from the design.
After passing below the main Glasgow to Edinburgh railway line at Castlecary, the motorway turns northwards, crossing the Forth and Clyde Canal. The canal underbridge was constructed in 2000 as part of a project to reopen it to navigation. Junction 6A is located immediately south of the canal and has north facing slip roads only. Junction 7, with connections to the A803, is full access and has seen little modification since 1974.
The motorway gains a running lane in each direction as it approaches the M876 at Junction 8. The routes are linked via east facing slip roads, allowing for north to south movements only.
The motorway continues through predominantly agricultural land for a further five miles before reaching the M9 at Junction 9. The southern section of this stretch, which was upgraded from an all-purpose dual carriageway, features discontinuous hard shoulders at some bridges.
Junction 9 is a large roundabout interchange with connections to the M9 southbound and the A91 and A872 towards Stirling. Stirling Services, operated by Moto and constructed in the mid-1980s, is also accessed from this part of the junction.
The M80 becomes the M9 a short distance later, with traffic wishing to continue towards Edinburgh forced to 'turn off to stay on'. Similarly, traffic travelling north on the M9 must merge with the M80 via a long slip road.
From the Archive
This article was first published in November 2020. Updated January 2023.