The M3 took nearly a quarter of a century to finish, and its final section was among the most fought-over stretches of road in modern Britain. The motorway opened in phases, from Lightwater and Bagshot to Popham in 1971, through to Winchester–Otterbourne Hill in 1995.
The delay was Twyford Down. The later stages drew opposition from environmental campaigns across Britain because of the large cutting driven through the wooded down, and a wave of road protests followed. The resulting sweep through the chalk is one of the more dramatic pieces of motorway landscape in England.
The road runs roughly 59 miles from Sunbury-on-Thames in Surrey to Eastleigh in Hampshire, meeting the M25 at Junction 2 and the M27 at Junction 14. It was built as dual three-lane throughout with one exception — between Junction 8 for the A303 and Junction 9 it drops to two lanes each way, a pinch point that still shapes how the road behaves on a busy summer Saturday heading for the coast.
59 miles
Total length
J1 – J14
Junctions
3
Service stations
Explore Every M3 Junction
Every junction on the M3 has its own dedicated guide page. Find nearby fuel stations, food options, hotels, pubs, supermarkets and more — all within easy reach of the motorway.
M3 Junctions
Click a junction to explore nearby places and facilities. Each junction has its own detailed guide.