M4 variable speed limit begins near Bristol
Variable speed limit signs on the M4 near Bristol have gone into operation.
The move is part of an £88m Highways Agency project aimed at making the motorway network around the city safer and enabling more reliable journey times.
Drivers will also be allowed to use the hard shoulder from November - when permitted by the overhead signals.
Variable limits will also come into force on the M5 in November with the hard shoulder usable from January.
The three-mile (4.8 km) section of the M4 stretches between junctions 19 (M32) and 20 (Almondsbury interchange).
On the M5 the managed section stretches between junctions 17 (Cribbs Causeway) and 15 (Almondsbury interchange).
Motorists can expect to see the hard shoulder opened during the daily rush hour and big events.