Motorists, businesses and residents are being warned about disruption as a major road is set to close for four weeks so a bridge can be improved.
Oxfordshire County Council's upgrade to the A338 around Grove Railway Bridge is part of a six-week scheme.
The work, starting 25 July, includes repairs and the installing of a fence on the northern side of the bridge.
The closure will extend from the Williams F1 roundabout to north of the junction with Bradfield Farm Cottages.
Bus services affected
Councillor David Robertson, Oxfordshire County Council's cabinet member for transport, said: "We are very grateful for the co-operation and understanding of the bus companies and we hope disruption will be kept to a minimum."
A diversion route will be signposted via East Hanney, Steventon, East Hendred, West Hendred, Ardington, Wantage and Grove, a council spokesman said.
The local authority will also fund shuttle buses to meet the services that may be disrupted.
The bus company Stagecoach will provide residents with information on the shuttle bus service, alterations to timetables on their buses as well as at affected bus stops, a council spokesman added.