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Route of the M45

The M45 is a spur from the M1 in Northamptonshire, westward towards Coventry. Today it just provides access to part of Coventry from one direction on the M1, and consequently it is, perhaps, not the most important motorway in Britain. But its historical significance is much greater: it was the original northern spur from the M1, and for a number of years it was part of the main road from London and the south-east to the West Midlands and the north.

It was built to connect the brand-new M1 to the A45 towards Birmingham, and performed a vital role in distributing traffic coming off the new motorway across the existing road network of the Midlands. But its heyday lasted only about twelve years. In 1971, the parallel section of M6 opened, connecting directly to the M1, and since then it's been a backwater. Once part of the signposted route from London to Birmingham and Coventry, today the signs on the M1 just point to "Coventry (S)". Its appearance is a little delapidated these days.

In its original form, the M45 was very basic, merging straight into the M1 at the eastern end, and taking a non-stop route to a roundabout on the A45 at the other. This left traffic on the A45 to pass through the village of Dunchurch, even though the motorway ran right past in parallel. In the 1980s, the village was bypassed by building a new junction with the A45 east of the village, allowing through traffic to use the motorway. Oddly, considering the terminal roundabout is grandly numbered junction 1, this junction has no number. Perhaps "0A" was not considered a suitable number for the road signs.


Start Kilsby (M1)
Finish Dunchurch (A45)
Passes None
Length 8 miles
Connects to M1


Views of the M45 from on and off the road. If you have a photo to contribute, contact me.


Northbound on the M1 approaching the M45. Given that the original bridge here was built to this width, a five lane carriageway plus hard shoulder must have been quite something in 1959. It's also quite excessive given how little traffic now exits onto the M45.
Photo by Dave Ryan


Eastbound, approaching the only real junction on the M45. It was actually added in the 1980s to allow the motorway to bypass Dunchurch.`
Photo by Steven Jukes

Construction Timeline

When the various parts of the M45 were built, listed in chronological order.

Open Jct Section
Nov1959 Entire motorway

Exit List

All the junctions and destinations along the route.

Junction   Westbound               Eastbound
12.4 km
Dunchurch Roundabout (Roundabout)

N/A More information about this junction
LanesLanesLanesLanesSigns LanesLanesLanesLanesSigns
8 miles, 2 lanes Up   Down 2 miles, 2 lanes
10 km A45 (Non-standard interchange) B4429 Daventry
More information about this junction
  Down 6 miles, 2 lanes
(M1 J17)
0.0 km
N/A M1


M1 Link
More information about this junction
LanesLanesLanesLanes LanesLanesLanesLanesLanesLanesLanes