The Dublin City Marathon will be the main cause of traffic disruption on Bank Holiday Monday, but its early start means much of the route will be open to traffic by late afternoon. The route is Westmoreland Street/Merrion Square North; Merrion Road; Nutley Lane; Stillorgan Road; Clonskeagh Road; Waterloo Road; Leeson Street; the Coombe; South Circular Road; Harold's Cross Road; Kimmage Road Lower; Kimmage Road West; Walkinstown Road; Davitt Road; Conyngham Road; Queen Street; Middle Abbey Street and O'Connell Street.
Other areas for drivers to avoid in Dublin over the weekend include Strand Road, Sandymount, which will be closed to traffic between Merrion Gates and Newgrove Avenue.
Construction will disrupt Gracepark Road, Drumcondra, and at Harold's Cross Road there will be diversions due to road works.
Old Naas Road will be temporarily closed between Main Street, Rathcoole to Beechwood. A oneway system remains in place on Leopardstown Road.
In Cork, Maylor Road and Caroline Street are closed until the end of the month. In Westmeath and Roscommon single-lane traffic will operate on the east-bound side of the Athlone bypass. The AA has asked drivers to take extra care here.
Wexford bridge is closed for essential repairs for four weeks.
Bus Eireann is expecting to carry 100,000 passengers over the weekend. Today and tomorrow the normal weekday schedule will operate. On Sunday, the normal Sunday schedule will operate, but special services geared to weekend travellers returning to major centres will be cancelled.
Cancelled Sunday services will operate on Monday. Monday services will operate to usual Sunday timetables.
A leaflet detailing the weekend services is available from Bus Eireann Travel Centres. A bank holiday telephone "hot-line" will be at 01-8366111.