Diversions, closures and speed restrictions
Check this page regularly for the latest updates on road closures, diversions, and speed restrictions
Current closures
18 May to 10 June - A1 northbound and A421 eastbound overnight closure
Overnight closures (9pm-5am) on:
- A1 northbound between Tempsford and Wyboston
- A421 eastbound between Renhold and Black Cat
Diversion
A1 northbound
- exit A1 at Tempsford Interchange onto St Neots Road
- take A428 towards Wyboston
- re-join A1 at Wyboston Interchange
A1 northbound diversion route map
A421 eastbound
- exit A421 at Cardington Interchange onto A603
- take A603 towards Sandy
- take A1 northbound at Sandy roundabout
18 to 22 May - A428 overnight closures between Eltisley north roundabout and Caxton Gibbet north roundabout
Closed overnight (8pm-6am) to install new footpaths, kerbs and for general road maintenance.
Diversion
- take A1198 north towards Papworth Everald
- exit onto B1040
- re-join A428 at Eltisley
A428 Eltisley north roundabout and Caxton Gibbet north roundabout diversion route map
26 to 28 May - Cambridge Road (Eltisley) overnight closures
Overnight closure (8pm to 6am) of Cambridge Road, Eltisley, for footpath and road resurfacing.
Diversion
Road users should exit Eltisley village by:
- the B1040
- onto the A428
29 to 30 May - A1 north and southbound, and A421 eastbound overnight closure
Overnight closures (9pm-5am) for signage, drainage and lighting work on:
- A1 northbound between Tempsford and Wyboston
- A1 southbound between Wyboston and Tempsford
- A421 eastbound between Renhold and Black Cat
Diversion
A1 northbound and A421 eastbound:
- exit A421 at Cardington onto A603 towards Sandy
- take A1 northbound towards Black Cat
- exit A1 northbound at Tempsford Interchange onto St Neots road
- re-join A1 northbound via A428 at Wyboston Interchange
See A1 northbound and A421 eastbound diversion route map
A1 southbound:
- exit A1 southbound at Wyboston Interchange onto A428 towards St Neots
- take Barford Road
- re-join A1 southbound at Tempsford
30 May to 1 June - A1 north and southbound weekend closure
Weekend closure of the A1 north and southbound at Black Cat between Wyboston and Tempsford from 9pm Saturday 30 May to 5am Monday 1 June 2026 for drainage works.
Diversion
A1 northbound:
- at Black Cat take A421 westbound towards Renhold
- exit A421 westbound at Renhold Interchanging looping back on the A421 eastbound
- re-join A1 northbound via A421 eastbound
See A1 northbound diversion route map
A1 southbound:
- exit A1 southbound at Wyboston Interchange onto A428 towards St Neots
- take Barford Road
- re-join A1 southbound at Tempsford
6 to 7 June - A1 northbound weekend closure between Tempsford and Black Cat
Weekend closure of A1 northbound between Tempsford and Black Cat from 5am Saturday 6 to 10pm Sunday 7 June 2026 for drainage works.
Diversion
- exit A1 northbound at Tempsford Interchange onto St Neots road
- re-join A1 northbound via A428 at Wyboston Interchange
12 - 15 June - A1 northbound and A1 southbound weekend closure
Weekend closure of the A1 northbound at Black Cat and A1 southbound between Wyboston and Tempsford from 9pm Friday 13 to 5am Monday 15 June 2026 for drainage works.
Diversion
A1 northbound:
- at Black Cat take A421 westbound towards Renhold
- exit A421 westbound at Renhold Interchanging looping back on the A421 eastbound
- re-join A1 northbound via A421 eastbound
See A1 northbound diversion route
A1 southbound:
- exit A1 southbound at Wyboston Interchange onto A428 towards St Neots
- take Barford Road
- re-join A1 southbound at Tempsford
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
Black Cat roundabout layout change - 24 November 2025
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
Caxton Gibbet road layout change - April 2026
From Monday 27 April 2026, we'll move traffic on the A428 onto a new stretch of road, linking with existing road networks.
These changes will help us build the upgraded junction and a new flyover bridge, which will carry the dual carriageway over the junction.
Traffic in both directions on the A428 (east of Caxton Gibbet) will be moved onto a new stretch of road, connecting directly to the northern roundabout.
Services at Caxton Gibbet will remain open and accessible.
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.
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Keep updated on the A428 Black Cat to Caxton Gibbet improvements
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