the road is a dual carriageway, most with two lanes each way, but there are two dual three-lane sections: on the newmarket bypass (between junctions 36 and 38) where it runs concurrent with the a11, and a short stretch between the girton interchange and bar hill. there are three at-grade junctions: with the b663 at bythorn in cambridgeshire (junction 15); at the leighton bromswold turn a few miles to the east (junction 17); and at the dockspur roundabout at the edge of felixstowe (junction 60).