The A40 between Abergavenny and Crickhowell will be closed overnight on October 26th in order to complete essential maintenance to a stretch of the road.

The closure will be enforced between 8pm and 6am, and the first total closure will be one of several during the construction period, which lasts until March 31st 2027. One lane of the road between Pyscodlyn Farm and the border between Powys and Monmouthshire at Glangrwyney will remain closed throughout the period, starting next Monday.

The imposed overnight closure on Monday night and Tuesday morning will mean diversions will be in place. For most vehicles, the diversion route will be via the A4077 towards Govilon, before joining the A465 Heads of the Valleys Road to get to Abergavenny.

However, due to the reduced weight limit on Gilwern Viaduct, which was imposed when engineers expressed their concerns about the structure of the bridge, some drivers will not be able to use this route.

The bridge has a three tonne weight limit, meaning any vehicle - including HGVs - could be sent on a diversion of 35 miles to get to Crickhowell if they are starting their journey from Abergavenny.

The official route for HGVs will be to follow the A465 all the way to Merthyr Tydfil before joining the A470 and driving the length of the Bannau Brycheiniog National Park to Brecon.

Traffic will then be able to rejoin the A40 from the town and drive south towards Crickhowell. For eastbound traffic the diversion will be vice versa.

Find out about planning applications that affect you by visiting the Public Notice Portal.

Drivers have been urged to plan ahead of they are using the route at night time, as well as allowing extra time for their daytime journeys where possible.