The busy road's being made two lanes in both directions between Segensworth and Titchfield - it's due to take 18 months.
Another No Car Zone In Southsea
Work starts today (Monday 27th February) on making the south end of Palmerston Road in Southsea a no-car zone.
The Portsmouth City Council project is designed to create a more welcoming environment for people on foot.
The plan is to boost the economy of the area, and improve walking links between Southsea's centre and the seafront.
The work includes raising the road and laying a more attractive surface, encouraging people to stroll and making the street more attractive to customers of local businesses.
The scheme includes many details suggested by local businesses, residents and disabled people's groups.
Work should be finished by June.
Cllr Mike Hancock, the council's Cabinet Member for Planning, Regeneration and Economic Development, said: "We're committed to making sure Southsea thrives as a unique area for eating out and specialist shopping, and that visitors make the most of its location near the seafront.
"We're sorry if this work causes anyone inconvenience, and we thank everyone for their patience while it takes place."
Cars will no longer be allowed from Osborne Road to the junction of Villiers Road. Drivers will need to use the following route instead:
* Osborne Road - Clarendon Road - Granada Road - South Parade - Clarence Parade. Buses, cyclists and loading vehicles will still be allowed.
The 5, 19 and 700 buses will be diverted via Clarence Parade during the work. Passengers heading for Southsea shops should change buses at The Hard interchange. Passengers leaving Southsea shops who need the 5 or 700 buses are advised to travel to The Hard Interchange on the 6/6A from Osborne Road.
The council's highways contractor, Colas, will be working from 8am to 5pm, Monday to Friday. No weekend work is planned.
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