There are some basic principles that you need to follow in Ireland to ensure a safe and happy trip, the first and most important principle, is that you drive on the wrong side of the road (ignore this principle if you are already driving on the wrong side of the road). Everything is backwards from the way you are used to driving, roundabouts, turns, gear shift. You should be able to master this after a couple of near head on collisions.
Sheep always have the right of way. They do a lot of damage to your car and you are probably tired of lamb stew by the time you hit one. Ditto for tractors, they are bigger than you, no further explanation necessary.
Advice for taking blind curves, hit the gas and close your eyes, the Virgin Mary you just saw on the side of the road will protect you.
Make sure you locate your reverse gear, you will need it when something bigger than you, say one of the thousand tour buses or tractors, demands the right of way on those cute country highways that purport to have two lanes but only if you are on a moped.
The most important role of the co-pilot is not to read the map nor is it finding a radio station that is not recounting the one major story that has broken in Ireland that day but rather to yell "left side of the road" "stay left" or any variation of that phrase as long as it contains the word left in it especially when a large tour bus is hurtling along aimed right at your vehicle.
The bridge across the Liffey on the M50, to the west of the city takes an astounding 3 euro if you do not have one of the payment methods already pre-set up. It's basically a complete cash cow.
News gets even worse if, for example, you are heading for the airport and forget to pay the charge - the extra late payment charges will mount up. Don't think you will get away with it either if you are jetting out - the car hire company can charge your creditcard. By the time they get around to it (if you havn't paid it over the internet or whatever) then it could result in quite a nasty little shock.
If you are travelling in peak hours or need to get around Dublin as quickly as possible then you have little option, but if you have time on your hands then head through the city centre for free.
Travel by car takes quite a bit longer than you'd expect. The width of the country is only 300 kilometers at the widest point. Galway to Dublin for example is about 210 km by road, but it takes about 3 hours to drive. There are very few divided highways and many country roads aren't wide enough for two cars to pass. Not to mention driving on the left side of the road!
We rented a compact car for about $20 US per day... most rental cars are manual transmission. Rental cars are available at the airport, but they are much cheaper downtown.
The central area of dublin (about a mile square) has now has a 30 kilometers per hour restruction slapped on it. I must admit that I never seem to have reached as high as that speed on the moving car park that is the North Quays, but I digress.
The council believes it will cut pedestrian injuries, and I hope it does. On the downside virtually everyone seems against it and it could infact increase the danger to pedestrians - druivers may becom frustrated and pedestrians may get 'caught out' by the speeding motorist when others are a bit slower.
As a tourist and a driver, just beware that if you are caught and they establish it is you in a hire car then the car hire company are at liberty to charge your credit card later.
Driving around Dublin was very difficult and confusing for us. There were many, many one-way streets, making it frustrating to navigate around the city. However, since we spent more time in the car looking for our destination than necessary, we left with a good idea of the city layout. It was like our own unplanned, accidental, indepth city tour!!
It's cheaper to get from Dublin to smaller Irish towns by bus.
National buses leave from Busaras on Store St, which is a 5-7 min walk from O'Connell bridge, down Eden Quay and turn right, go under the overhead Smirnoff bridge, cross the street and there you are.
There are 4 Motorways around Dublin :
M1 - from Whitehall suburb to Dublin Airport, then to Belfast
M50 - Also known as HELL. Avoid this in the mornings and evenings where possible.
Basically it's the Dublin city bypass or ring-road, from the M1 junction through Ballymun, Blanchardstown, Clondalkin, Tallaght, Ballinteer to Shankill. Toll bridge after the Blanchardstown exit -€1.80 fee.
M 11 - From Shankill to part of County Wicklow, this route takes you to County Wexford.
M7 - Limerick/Cork/Waterford road to Dublin. Starts 30 miles away from Dublin and stops just after the Dublin/Kildare border.
Driving - A nightmare. Dublin's ancient street design and the absence of any intelligent traffic management authority means Dublin is prone to gridlock. Parking is problematic too. Street parking is expensive where permitted. Multi-storey carparks are plentiful enough however and electronic signposts around the city advise of available spaces. It is forbidden to drive in bus lanes of course, but a lot of bus lanes revert to normal traffic usage after a certain time so keep an eye on the signposts!
Ok....this is really for anyone that is used to driving large distances (like around Australia). Ireland is a small, beautiful island, but driving around it is immensely frustrating. In some parts (like the drive from Dublin to Limerick or Killarney, you will easily need to budget for 2-3 hrs longer than you think).
Just make sure to give yourself plenty of time!!