Motorists in Kerry will be directed to drive "clockwise" around Dingle's Ceann Sléibhe from Friday, for a three-week trial period.
The 47km Slea Head Drive, on Ireland's most westerly peninsula, has experienced long tailbacks and fraught tempers for many years.
Gardaí have regularly been called to the scene of confrontation between buses, camper vans, coaches and SUVs trying to edge past each other on the narrow headland.
In 2017, locals were asked by the Dingle Chamber of Commerce to "modify their day" and not to venture out at peak traffic times.
"Something had to be done," said Independent councillor Johnny Healy-Rae as he welcomed the move by Kerry County Council and Fáilte Ireland.
Cllr Healy-Rae had long called for measures, including a one-way system and traffic lights.
At just 3m wide, the R559 is too narrow to allow large vehicles to pass and council workers, as well as gardaí, were regularly at the scene. Large coaches of tourists had to reverse for kilometres, he recalled.
The clockwise traffic management system is in place for visitors from Friday 29 July until Monday 22 August.
"During this trial period, the council asks that larger vehicles travel in a clockwise direction around Slea Head, starting at Dingle town, then on to Ventry, Slea Head, Coumeenole, Dunquin, Ballyferriter, Muríoch, Feohanagh and back to Dingle," a spokesman said.
It is said the trial, which is taking place during the peak visitor season, will inform future considerations on traffic management in the area. The previous trial was deemed a success.
Measures are being put in place to guarantee the correct direction is followed, with signage advising of the clockwise system being erected locally.
"A Kerry County Council employee will be positioned each day from 10.30am to 4pm at Coumeenole to encourage larger vehicles that are driving in the incorrect direction to follow the correct route," the council said.
Visitors will be encouraged to follow the recommended route from the outset "resulting in more time to relax and enjoy the magnificent views, attractions, history and culture of this beautiful part of Kerry", the spokesman said.
Local access will be maintained as normal.
