A421

The A421 will carry the weary traveller from a point near Banbury to Milton Keynes, Bedford and St Neots, a country road through the villages and towns of Buckinghamshire and Bedfordshire.

At its eastern end, it suddenly becomes something much more important, and the part we're interested in here runs from the M1 at Ridgmont to the A1 at the Black Cat Roundabout.

The expressway between those points is relatively new, and as recently as 1995 Bedford was an important county town stranded between the M1 and A1 with no particularly good connection to either. Since 1996, three sections of new dual carriageway have been built, progressively completing a fast route that serves to link Cambridge to Milton Keynes and Bedford to the wider world.

As good as this new expressway is, it's let down by its two terminal junctions - both of which, in fact, feature in our Bad Junctions list. The Black Cat Roundabout is just a nasty flat roundabout that's been overloaded for years, but particular merit is awarded to M1 J13 Ridgmont Interchange which was modified in 2010 from a tiny diamond junction to the monstrous calamity that stands there today. A fast new road surely deserves better connections to the rest of the road network than these.

It's hard to escape the fact that much traffic on this road continues east of St Neots to reach Cambridge and the A14, and that at least half of that is also a high-quality, brand-new expressway. There's only nine miles, as the crow flies, between the end of this road at Black Cat and the start of the A428 expressway at Caxton Gibbet.

You're not looking at the whole A421

This page is about the parts of the A421 that are designated a motorway or that have motorway characteristics. Other sections of this road will not be featured here and will not count towards the length of the road as shown below.

Start

St Neots

End

Milton Keynes

Passes

Bedford

Connects to
Length

18 miles

Exit list

Symbols and conventions are explained in the key to exit lists. You can click any junction to see its full details.

Junction   Eastbound               Westbound  
28.5 km The NORTH
Peterborough A1 Link
Cambridge (A428)
London
Stevenage A1 Link
Great Barford






A1
(A428)
EAST







A1
N/A
LanesLanesLanesLanes Signs LanesLanesLanesLanes Signs
4.5 miles, 2 lanes 4.5 miles, 2 lanes
21.5 km Bedford
A428
Great Barford
A428 Bedford
A428
Great Barford
LanesLanesLanesLanes LanesLanesLanesLanes
2.5 miles, 2 lanes 2.5 miles, 2 lanes
17.8 km Sandy
Bedford
A603
A603
(A600)
A603 Bedford
Sandy
A603
Hitchin
Shefford
(A600)
LanesLanesLanesLanes LanesLanesLanesLanes
0.8 miles, 2 lanes  
16.1 km Hitchin
Shefford
Bedford
A600
A600 A600
LanesLanesLanesLanes
1.8 miles, 2 lanes 2.6 miles, 2 lanes
13.3 km Luton A6
Bedford
Elstow
A5141
A5141 A6 Bedford
Luton
A6
LanesLanesLanesLanesLanes LanesLanesLanesLanesLanes
1.3 miles, 3 lanes 1.3 miles, 3 lanes
11.4 km Northampton
A428 (A6)
Bromham
Kempston
B531

A428
(A6)
Northampton
A428 (A6)
Bromham
Kempston
LanesLanesLanesLanesLanes LanesLanesLanesLanesLanes
3.4 miles, 2 lanes 3.4 miles, 2 lanes
5.9 km Cranfield
Marston Moretaine
Cranfield
Marston Moretaine
LanesLanesLanesLanes LanesLanesLanesLanes
3.7 miles, 2 lanes 3.7 miles, 2 lanes
M1 J13
0.0 km
N/A M1










A421
WEST
A507

M1











Ampthill
Ridgmont A507
London
M1 Link
Husborne Crawley
Milton Keynes
A421
The NORTH
M1 Link
Cranfield
LanesLanesLanesLanes LanesLanesLanesLanes
LanesLanesLanesLanes
Routes

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