Nine months of roadworks at the Seven Dials roundabout in Brighton are due to start on Monday 4 March.
Letters have been sent to about 7,000 homes in the surrounding area by Brighton and Hove City Council.
The council said that the work would be phased to try to minimise disruption. A schedule is available on the council’s website at www.brighton-hove.gov.uk/sevendialsproject.
The works are expected to last about nine months, ending in December.
Several surrounding roads will be closed or partially closed for three to four weeks at a time. The council aims to close roads in rotation rather than all at once.
The changes include creating a longer oval traffic island to replace the current mini-roundabout.
The council said that this would improve safety at the Seven Dials. It said that traffic engineers believed that this would mean that vehicles would merge more gradually at the roundabout.
The changes are intended to benefit all road users particularly cyclists and pedestrians.
Other measures include removing guard railings and street clutter and changing pelican crossings to zebra crossings to make it quicker and easier to cross.
The council said that experts believed that removing the current guard railings would not make the roundabout less safe.
The Seven Dials has one of the worst accident records in Brighton and Hove.
The council said that 23 people were injured in 20 accidents within about 25 yards of the Seven Dials from October 2009 to October last year.
Councillors approved the changes to the Dials in January.
Councillor Ian Davey, the chairman of the council’s Transport Committee, said: “We apologise for any disruption caused but are confident that that once the works are complete people will appreciate the improvement.
“The schedule has been planned to keep nuisance and disruption to a minimum.
“We’re seriously committed to addressing any concerns people raise during construction.”
The contractor Edburton will have a site office fenced off on the grass in front of Montpelier Crescent. It will have to make good the turf after the roadworks are completed.
Anyone experiencing problems with the works can email firstname.lastname@example.org.
The council said: “In cases of extreme difficulty call the council’s highways centre on 01273 292929.”