The preferred route of a new road linking Oxford and Cambridge has been announced.
Transport minister Jesse Norman said the Oxford-Cambridge Expressway will run alongside the planned East West rail line, to give consumers "a variety of road and rail travel options".
The Department for Transport said scrutiny of three options revealed that a central corridor would offer the most benefits to the region by providing better links to jobs, education, leisure facilities and health services.
The road, with options to pass either west or east of Oxford, is expected to cut up to 40 minutes from journeys between the M4 and the M1.
The preferred route rules out construction in the area of the Otmoor nature reserve, demonstrating the Government's "desire to protect the natural environment", Mr Norman said.
The expressway will fill "a major gap in the national road network" and, alongside the rail link, will "help unlock the commercial development of up to one million new homes", according to Mr Norman.
He added that the projects will bring hundreds of thousands of people "within reach of high-quality jobs in centres of rapid growth such as Oxford Science Park".
The design of the road will be put to public consultation next year. It is scheduled to be open to traffic by 2030.