Motorists are being told to expect delays over the Bank Holiday weekend in the Falcarragh / Dunlewey and Gweedore areas.
There are a number of sporting events and Gardai have said restrictions will be in place.
The Gaelforce North race will take place tomorrow, and motorists travelling along the R251 (The Termon to Dunlewey Road) between 9am and 4pm can expect delays from the Churchill junction to Dunlewey.
There will especially be delays at Mount Errigal and a stop system will be in place.
Motorists are also asked to take care as a cycle race will be in progress along this route.
Traffic along the N56, Letterkenny to Dungloe road may also experience some delays on Saturday and Sunday due to an expected large volume of traffic as a result of the All Ireland GAA Gaeltacth championships which are taking place in Falcarragh.
Motorists who are not attending this event are asked to avoid Falcarragh to prevent delays.
Meanwhile, in South Donegal, thousands have gathered for the Rory Gallagher Festival in Ballyshannon.