A428 Upgrade - Weekend Closures & Overnight Works Next Week

Drivers are being warned of significant road closures and diversions this weekend as part of the £1 billion A428 upgrade project being carried out by National Highways.

A428: Caxton Gibbet to Cambourne

A contraflow system is being installed on the A428 east of Caxton Gibbet roundabout towards Cambourne. To allow work to take place safely, the A428 will be fully closed in both directions from 8pm Friday 3 October to 6am Monday 6 October 2025.

Traffic will be diverted to join the M11 Southbound, then via the A603, before rejoining the A1198

The closures are part of a wider series of works to improve safety, traffic flow, and infrastructure along the busy corridor.

FROM MONDAY:

A1198: Utility Ducting and Island Removal

An overnight closure will be in place on the A1198 to allow workers to install utility ducting and remove the central traffic island. The work, which involves laying protective tubes for electricity, broadband, water, and gas utilities will take place between Caxton Gibbet roundabout and the entrance to Caxton Gibbet services.

Diversions will be:

• East along the A428

• South on the M11

• Rejoin the A1198 via the A603

A421: Safety Barriers and Lighting near Black Cat Roundabout

Further work is planned on the A421 eastbound near Black Cat roundabout to install new safety barriers and lighting. In addition, Anglian Water will connect a new water main on Nags Head Lane near the A1 carriageway. 

Closures and diversions are as follows:

• A421 eastbound: between Renhold interchange and Black Cat roundabout

• A1 northbound: between Tempsford and Wyboston

Dates:

• Monday 6 to Friday 10 October (9pm to 5am)

• Weekend closure: Friday 10th to Monday 13 October (9pm to 5am)

Diversion route:

• Off the A421 at Cardington Interchange onto the A603 towards Sandy

• At Sandy, onto the A1 northbound to Tempsford Interchange

• Exit onto St Neots Road to join the A428 at St Neots

• Re-join A1 northbound at Wyboston junction

National Highways says these closures are essential to ensure the safety of workers and road users while progressing the major upgrade of key routes in the region. Drivers are advised to plan journeys in advance, allow extra travel time, and follow diversion signage.