One of Derby's busiest junctions, The Five Lamps junction, will be closed from today for major reconstruction works. It will force lengthy diversions around the city.
The improvements, costing £185,000, will mean that traffic will not be able to exit the city via Garden Street or use Kedleston Road.
People coming out of the city centre will be diverted around the inner ring road and on to Ashbourne Road to Markeaton Island.
Drivers going into the city will be diverted around Broadway and back in along Duffield Road.
The council says the flow of traffic won't be any worse than during a normal rush hour during school term times.
It's thought that during a normal 24-hour period, 32,000 people use the Five Lamps junction.
The work will take over two weeks to complete.