Thousands of motorists are to face delays and diversions this weekend as a section of the A14 is closed.
The old A14 bridge was demolished in June
The A14 near Kettering, Northants, will be shut between junctions 7 and 8 until 0600 BST on Monday so that a new bridge can be swung into place.
The bridge is part of a junction providing an interchange for villages to the south of the A14.
The Highways Agency said all diversions are clearly signposted for motorists but advised avoiding the area.
When the road shut in June for the bridge to be demolished there was chaos in Kettering town centre as roadworks in Northfield Avenue coincided with the closure.
Other roadworks suspended
Although highway bosses have pledged to suspend all other roadworks in the town for the weekend, long delays are expected.
The impact of the A14 closure is also expected to affect motorists heading to and from Northamptonshire and Cambridgeshire.
Traffic travelling east will be diverted off the A14 at junction 7, along the A43, A6003 and A6014 to Corby.
Traffic on the M1 and M6 will be diverted to junction 15 of the M1, along the A45 to Thrapston to rejoin the A14 at junction 13.
A giant crane with a 300-tonne capacity will begin to swing 12 large steel bridge beams over the A14.
These beams will be lifted in pairs to construct the four main spans of the bridge.
Highways Agency project manager Geoff Chatfield said: "Constructing the bridge in this way means that we can complete the work in just one weekend to minimise disruption."