WORK has begun on creating 500 extra parking spaces at Thornhill Park- and-Ride.
Oxfordshire County Council said it commissioned the work because the 855-space site was the only park-and-ride in Oxford which was consistently full at 9am.
The £3.6m project is due to be finished in August this year, but the first new spaces should be available from late spring.
The new spaces will be created in a field to the east of the site, on the left as motorists enter the car park.
County council cabinet member for transport Rodney Rose visited the site on Thursday and had a go at operating a JCB to get work under way.
He said: “This park-and-ride not only attracts what it was designed for, which is commuters, but also passengers for the Oxford Tube, the X90 and buses going to Heathrow and Gatwick airports.
“It is sometimes full as early as 8am, and if people come here and can’t park then it is not serving its purpose.
“While there is strong demand at all five park-and-ride sites, Thornhill experiences the greatest pressure, with the car park often filling up to capacity in a short space of time.”
The internal layout of the site will also be changed, to improve the vehicle exit to London Road.
Cycle parking will be relocated to provide safer, traffic-free access to the site and the short-stay parking area will be improved to try to stop drivers doing U-turns in the access road.
Oxford Brookes graduate Lindsay Rogers, 26, from Thame, said she used to park at Thornhill every day to catch the bus to university. She said: “If you get here before 10am you can get a space, but between 10am and midday there is no hope.”
Parking at Thornhill is currently free up to 11 hours, but costs £3 between 11 and 24 hours, and £3 for every additional 24 hours after that, up to a maximum 72 hours.
However, the county council recently announced it would be scrapping free parking as of April this year, and introducing charges for up to 11 hours.
The exact rates have yet to be decided, but councillors said the charges should be in line with the £2 charge at the city council-run park-and-ride sites, Pear Tree, Seacourt and Redbridge.