A 60-mile diversion on the M27 is the ‘biggest ever seen’ in the country.
The motorway will be closed in both directions between Junction 3 and Junction 5 from Friday night and Monday morning.
Highways England are closing the M27 to demolish the Romsey Road bridges and replace them.
ITV news has reported in a tweet that the 60-mile diversion via Salisbury is the ‘biggest ever seen' not just in the south but in the country.
Why is the M27 being closed?
The motorway will be shut this weekend for roadworks on the Romsey Road Bridge. The 40-year-old bridge is nearing the end of its life and is in need of replacement.
The only safe way to do this is to close the motorway while this takes place.
The Romsey Road Bridge is well used and carries tens of thousands of vehicles daily.
The bridge is actually made up of two individual bridges, both will be closed for three full weekends while the existing bridge is demolished and a new one installed.
The replacement bridge has a different design and will have a lifespan of 120 years.