Coventry–Northampton The road starts on the
A4600 Sky Blue Way in Coventry, heading eastbound out of the city and meeting the A444 and A4082 roads before crossing the
A46 Eastern Bypass and into
Warwickshire. The road then passes through the village of
Binley Woods before becoming more rural in nature, meeting the
Fosse Way and crossing the
River Avon at
Bretford. further along, the road enters
Rugby where it meets the A4071 and
A426 and passes
Rugby School. It then continues out of the town to the east through the suburb of
Hillmorton and crosses the
A5 near
Daventry International Rail Freight Terminal (DIRFT). It meets the M1 at its original terminus, junction 18, and bypasses the towns of
Crick and
West Haddon. The road passes the
Althorp family estate, then enters
Northampton.
Northampton–Cambridge East of Northampton, the road passes
Little Houghton,
Brafield-on-the-Green and
Yardley Hastings. After here it enters the
City of Milton Keynes (and
Buckinghamshire) where it meets the
A509 at Warrington roundabout. Continuing towards Bedford, the road passes
Lavendon and
Cold Brayfield. Crossing the
Great Ouse it enters Bedfordshire at
Turvey, on to
Bromham. It meets the
A422 at a roundabout outside
Bromham. The road bypasses Bromham and, leaving behind its former route east-bound through Bedford (which has become the A4280), swings southwards on a new alignment then, via a new bridge over the Great Ouse, merges with the A421 south of
Kempston. The A428 loses its identity here: the route continues as the A421 as it bypasses Bedford,
Great Barford and
Roxton and goes on to become the dual-carriageway
A1 at the
Black Cat roundabout. Heading north, the route leaves the A1 via a
grade separated junction just south of
St Neots and regains its identity. Crossed by the
East Coast Main Line, it leaves Bedfordshire for Cambridgeshire. The A428 from here to Cambridge follows the former A45, which became the A428 when the
A14 opened. It meets the
A1198 (former A14) at
Caxton Gibbet roundabout near
Papworth Everard. From here the road is dual carriageway, bypassing the existing single carriageway section near
Hardwick. The route terminates, merging into the A14 at
Girton interchange, where traffic joins first from the M11 junction 14 and then from the trunk A14 road junction 31. ==Work in progress==