The pedestrianisation of Tenby's walled town is to start on Monday - two weeks earlier than usual, as part of a new trial.
The trial also sees the pedestrianisation period being extended to Friday, September 11 - one week later than usual - and ending at 5.30 pm daily instead of 5 pm.
Clr. Rob Lewis, cabinet member for transportation for Pembrokeshire County Council, said: "The scheme intends to support local businesses and town council initiatives aimed at regenerating the town centre by building on the successful existing pedestrianisation scheme.
"It will be fully reviewed later in year to determine whether it should be made permanent."
Proposals for the trial extension were backed by the county council's cabinet in April this year.
It followed a consultation with residents and businesses within the walled town, which was also available online for anyone wishing to comment.
A total of 59 per cent of the respondents said they 'strongly agreed' or 'agreed' with the proposal to extend the scheme by three weeks, and 36 per cent 'strongly disagreed' or 'disagreed.'
Fifty-seven per cent 'strongly agreed' or 'agreed' with extending the finish time from 5 pm to 5.30 pm, while 36 per cent 'strongly disagreed' or 'disagreed.'
A Park and Ride service will operate on a free basis this year from the Salterns car park only. The service will start slightly later on July 18 when the school holidays start, and continue for an extended period up to the September 11, which is also the weekend of Ironman Wales.