Drivers face three weeks of disruption as a busy section of dual carriageway closes for maintenance and repairs.
The eastbound A35 Christchurch bypass in Dorset will be shut from Fountain Way roundabout from 18:00 GMT on Monday until 06:00 on 10 November.
It will close westbound from Somerford Roundabout between 18:00 on 10 November and 06:00 on 17 November.
The official 30-mile diversion is an hour-long route via the A338 Wessex Way, the A31 at Cadnam and the A35 via Ashurst and Lyndhurst in Hampshire.
The work includes major resurfacing of the A35 Stony Lane/Purewell Cross roundabout, a section of dual carriageway from Fountain roundabout to the southern end of the B3347 Stony Lane.
Other work includes installation of a visibility screen at Purewell Cross, vegetation clearance, sign renewal, litter picking, gully cleaning, crash barrier repairs, bridge parapet repairs over the River Mude and gas mains repairs by Southern Gas Network in Stony Lane.
Bournemouth, Christchurch and Poole Council member for highways Andy Hadley said: “The diversion route for these essential works is extensive due to the requirement for diverted A-road traffic to use another suitable A road.
“That and weight restrictions on some routes means the main diversionary route sends vehicles, with the focus on HGVs, on a 30-mile diversion.
“However, other routes are available as usual. We would ask that you do not use Burley as a shortcut, as roads there are suitable for local access only.”
Waitrose car park and Millhams Street North will be unaffected.
Christchurch Market and market bus services will operate as normal on Mondays, with work pausing on those days.
