A1 and A421 closures in the coming week

Highways diversion routes

National Highways have advised Richard that the A1 will be closed northbound between Tempsford and the Black Cat roundabout from 9pm on Friday 17th until 5am on Monday 20th October.

Traffic will be diverted as follows:

  • off the A1 at Tempsford.
  • onto St Neots Road and joining the A428 at St Neots.
  • re-join the A1 northbound at the Wyboston junction. 

The A421 westbound will be closed between Black Cat roundabout and Renhold interchange, and the A1 northbound between Tempsford and Wyboston, and Bedford Road overnight on the following dates:

  • Wednesday 15th to Friday 17th October 2025 (9pm to 5am)
  • Monday 20th to Friday 25th October 2025 (9pm to 5am)

Traffic will be diverted as follows:

  • continue south on the A1 towards Sandy and then travel west on the A603 towards Bedford
  • rejoin the A421 at Cardington interchange

A map of both diversion routes can be seen below.

A1 diversion route
  • A1 & A421 diversion route

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