The
M27 is a
motorway in
Hampshire, England. It is long and runs west-east from
Cadnam to
Portsmouth. It was opened in stages between 1975 and 1983. It is unfinished, as an extension to the east was planned. A number of smaller motorways were proposed, connecting the city centres of
Southampton and Portsmouth to the motorway; of these only the
M271 and
M275 were built. Two sections of the M27 have since been widened to four lanes each way, the first between Junctions 7 and 8, and the second between Junctions 3 and 4.