Diversions, closures and speed restrictions

Check this page regularly for the latest updates on road closures, diversions, and speed restrictions

Current closures

Works

We'll be installing new lighting columns on the A1 northbound.

Closure

We'll close the A1 northbound between Tempsford and Black Cat roundabout overnight (9pm to 5am) from Monday 26 to Friday 30 January 2026.

Diversion

exit A1 northbound at Tempsford junction
take St Neots Road towards St Neots
join A428 towards Wyboston
re-join A1 northbound at Wyboston junction

See A1 northbound overnight closures diversion route map

Works

We are installing new street lighting, permanent signage, and CCTV on the A421 eastbound.

Closure

We'll close the A421 eastbound between Renhold Interchange and Black Cat junction overnight (8pm-5am) from Monday 2 to Saturday 7 February 2026

Diversion

exit A421 at Cardington Interchange
follow A603 towards Sandy
join A1 northbound at Sandy towards Black Cat junction

See A421 eastbound diversion route map

2 to 13 February - Potton Road closure

Works

We are installing new drainage, kerbs and resurfacing for the realignment of Potton Road.

Closure

We'll close Potton Road from Rectory Farm to the south of Eynesbury Plant Hire from 9:30am Monday 2 to 9pm Friday 13 February 2026.

Diversion

take B1046 towards Abbotsley
continue south on Pitsdean Road

See Potton Road closure diversion route map

Works

We are lifting beams into place on a new bridge at Kelpie Marine over the A1.

Closure

We'll close the following roads from 9pm Friday 6 to 5am Monday 9 February 2026:

A1 northbound between Tempsford and Black Cat junction
A421 westbound from Black Cat junction to Renhold

Diversion

A1 northbound

exit A1 at Tempsford Interchange onto St Neots Road
take A428 towards Wyboston
rejoin A1 at Wyboston Interchange

A421 westbound

continue south on A1
take A603 towards Bedford
rejoin A421 westbound at Cardington Interchange

See A1 northbound & A421 westbound diversion route map

Works

We are installing new street lighting, permanent signage, and CCTV on the A1 southbound.

Closure

We'll close the A1 southbound between Wyboston and Tempsford overnight (9pm to 5am) from Monday 9 to Saturday 14 February 2026.

Diversion

exit A1 at Wyboston Interchange
take A428 towards St Neots
rejoin A1 at Tempsford Interchange

See A1 southbound diversion route map

Works

We're installing rigid grids close to the A421 westbound.

Rigid inclusions are strong columns installed in the ground to strengthen weak soil, helping keep embankments and structures stable and reducing the risk of uneven settlement.

Closure

We'll close the A421 westbound between from Black Cat junction and Renhold Interchange from 9pm Friday 13 to 5am Monday 16 February 2026.

Diversion

continue south on A1
take A603 towards Bedford
rejoin A421 westbound at Cardington Interchange

See A421 westbound diversion route map

Works

We will tie in the new Potton Road and B1046 layout with the existing local road network. This includes installing new drainage, kerbs and resurfacing.

Closure

We will close the following roads from 9pm Friday 13 to 6am Monday 23 February 2026:

Potton Road from the B1046 junction to south of Eynesbury Plant Hire.
B1046 from Potton Road rail bridge to Lansbury Farm.

Diversion

head south on Barford Road taking the first exit onto the A428 eastbound
continue on A428 towards St Neots and then onto south on B1046 at Eltisley
take Gransden Road and then rejoin St Neots Road

See Potton Road & B1046 closure diversion route map

Works

We are installing new street lighting, permanent signage, and CCTV on the A421 westbound and Bedford Road.

Closure

We'll close the following roads overnight (9pm to 5am) from Monday 16 to Saturday 21 February 2026:

A421 westbound between Black Cat junction and Renhold Interchange.
Bedford Road between Roxton Garden Centre and Black Cat roundabout.

Diversion

continue south on A1
take A603 towards Bedford
rejoin A421 westbound at Cardington Interchange

See A421 westbound diversion route map

Works

We're installing rigid grids close to the A421 westbound.

Rigid inclusions are strong columns installed in the ground to strengthen weak soil, helping keep embankments and structures stable and reducing the risk of uneven settlement.

Closure

We'll close the A421 westbound between from Black Cat junction and Renhold Interchange from 9pm Friday 20 to 5am Monday 23 February 2026.

Diversion

continue south on A1
take A603 towards Bedford
rejoin A421 westbound at Cardington Interchange

See A421 westbound diversion route map

Works

We're construction a new bus stop on the A1 northbound.

Closure

We'll close the following roads overnight (9pm to 5am) from Monday 23 to Saturday 28 February 2026:

A1 northbound between Tempsford and Wyboston.
A421 eastbound between Renhold Interchange and Black Cat junction.

Diversion

A1 northbound

exit A1 at Tempsford Interchange onto St Neots Road
take A428 towards Wyboston
rejoin A1 at Wyboston Interchange

A421 eastbound

exit A421 at Cardington Interchange
follow A603 towards Sandy
join A1 northbound towards Black Cat junction

See A1 northbound & A421 eastbound diversion route map

Works

We're installing rigid grids close to the A421 westbound.

Rigid inclusions are strong columns installed in the ground to strengthen weak soil, helping keep embankments and structures stable and reducing the risk of uneven settlement.

Closure

We'll close the A421 westbound between from Black Cat junction and Renhold Interchange from 9pm Friday 27 February to 5am Monday 2 March 2026.

Diversion

continue south on A1
take A603 towards Bedford
rejoin A421 westbound at Cardington Interchange

See A421 westbound diversion route map

Works

We’ll be installing key components of the new flyover at Caxton Gibbet, including:

lifting and placing 11 bridge beams over the A1198
installing glass-reinforced plastic (GRP) panels between the beams to form the base of the new bridge deck
fitting temporary safety barriers to keep the bridge deck work area safe and secure during construction

Closure

We'll close the A1198 between Caxton Gibbet roundabout and Caxton Gibbet North roundabout overnight (8pm-6am) from Monday 16 February to Saturday 7 March 2026.

Diversion:

A428 traffic to head east joining the A14 at Histon
take A14 towards Godmanchester
re-join A428 by A1198

See A1198 closure diversion route map

Please remember that closures can change at short notice. You can check the latest information on our daily closures page or find live travel information on our Traffic England site. Our travel alerts give details of live incidents on our network.

Long term changes

From Monday 24 November, we'll open new sections of road at Black Cat roundabout, linking with existing road networks.

A1 southbound

We’re moving the A1 southbound onto a new stretch of road passing under the new east bridge at Black Cat roundabout.

Make sure you’re in the correct lane before you reach the junction:

left hand lane for A1 south, A421 or M1
right hand lane for A1 north, A421 or M1

A1 northbound

We’re moving the A1 northbound approach onto the new northbound on-slip at Black Cat roundabout.

Make sure you’re in the correct lane before you reach the junction:

left hand lane for A421 west and Bedford Road
right hand lane for A1 north

Map of Black Cat roundabout layout from November 2025.

Let us know what you think

Use our A428 Black Cat to Caxton Gibbet improvements feedback tool to have your say.

This tool features an interactive map, allowing you to click on specific locations to leave targeted comments or provide general feedback.

ECHO is a one-way feedback tool, so if you'd like a response to your feedback you can email the project team at info@a428.co.uk.

Planning diversions, traffic management and speed limits

What you can expect to see

The A1, A421, and A428 will mostly stay open while we carry out our work.

There may be some overnight and full weekend closures from time to time. We'll need these for important tasks like:

connecting new and existing roads
building bridges
delivering large pieces of equipment or materials.

We're committed to being a good neighbour. That’s why we’re carefully planning our work to reduce any disruption to drivers and the local community.

Highest safe speed through roadworks

We’ve determined that a temporary speed limit of 40mph is needed to keep both road users and our workers safe.

This reduced speed limit helps junctions function as usual, which means we won’t need to close roads as often

How we choose diversion routes

We're dedicated to ensuring that any traffic diversions around road closures are safe and appropriate. We'll use diversion routes that can handle the type and amount of traffic being redirected.

The diversion routes will mainly follow major A roads to avoid heavy traffic on local streets. We'll work with local authorities to agree on the best routes.

These diversions are required by law, based on the development consent order (similar to our official approval or planning permission).

To minimise disruption, we will manage traffic carefully, providing clear signs and advance warnings to drivers.

Sign up for updates

Keep updated on the A428 Black Cat to Caxton Gibbet improvements