Drivers are being being warned of major roadworks which are expected to cause delays in the Lincoln area.
The improvements aim to strengthen the Newark Road bridge and will replace the traffic signals at the St Catherine's and South Park roundabout.
On Monday work began to divert water and gas mains. At the end of April Newark Road will close for four months.
Area highways manager Mark Welsh said efforts were being made to minimise disruptions as much as possible.
He said: "The work has to be done, bridges have to be replaced and at the Cross O'Cliff Hill and St Catherine's junction the signals need replacing and the road there is failing, so we have to reconstruct that road.
"A lot of that work, in the second phase of the work...will be done at night but there will be some divisions also."
The Newark Road area is one of the main western approaches to the city.