The final stretch of the M9 Dublin-Waterford route opened today, bringing the total journey time to 90 minutes. But how much else do you know about Ireland’s road network? Did you know that Ireland boasts the world’s first ever recorded road fatality? Or that taxpayers’ money goes to fund otter lovespots?

No, we thought not.

1.     Ireland’s most expensive road project is the M3, which cost €1 billion. But the road which cost most on a euro-per-kilometre basis is the Dundrum bypass. A mere 1.2km of roadway simply to decongest the main street of one Dublin suburb cost €44.4m – that’s €37 million per km or €1,269 for every inch of road. All but €11.4m went to compensate those whose property had to be acquired to build the road.

2.     The road which has taken longest to complete is the M7 Dublin – Limerick route. It started life as the Naas Road in 1963 and is STILL under construction, with 120km of it completed so far. That’s an average of 2.5km a year. It’s  due for completion by the end of this year when the Limerick to Nenagh stretch is finished. The M50 was technically even slower  – it’s 32 km long, was first proposed in 1971, and took over 23 years to build – which means it was built at a rate of 1.3 km per year.

3.     You can leave Newlands Cross in Dubin and drive all the way to the Dunkettle interchange in Cork, without passing a toilet facility or petrol pump. That’s a distance of 240km.

Plans are in place for 12 full services areas – so you’ll eventually never be more than 60km from one. Two are to open on the M1 at Castlebellingham and Lusk, and one on the M4 at Enfield in October. According to the NRA, they’ll be so good, you’d go there for your holidays.

4.     We may not boast the best road infrastructure in Europe, but we do have an unparalleled animal infrastructure. Every time a new road is built, infrastructure also has to be put in place to allow wildlife species to complete their daily commute in safety. We have badger ways; otter ledges; rope ladders for squirrels and pine martens; mammal fences; and there are even bat houses built along on the Ennis bypass. Artificial breeding grounds  have also been constructed for otters.

5.     One per cent of the cost of every new road is set aside to fund a piece of art, up to a cap of €64,000, under the Per Cent for Art scheme. The local authorities decide on a theme and are responsible for commissioning the work. Some of the more famous pieces of roadside art include Architects of the Land, limestone figures of a man and a bull, one each side of M7 Nenagh Bypass. Colin Grehan created the sculpture in 2001 from two massive limestone blocks. Gaelic Chieftain by Maurice Harron is a striking sculpture of a horse and rider made from what looks like scrap metal in Boyle, Co Roscommon.

6.     We drive on the left because of an edict issued by Pope Boniface the Eighth in the year 1300. He instructed all pilgrims to pass each other right side to right side, or swordarm to swordarm. But when Napoleon came along, he decreed that his troops should march on the right in defiance. Since we were one of the few countries not conquered by Napoleon, we stayed on the left.

7.     There are between eight and ten different types of speedbumps  in Dublin: the capital’s roads were basically used an experiment to see which type worked best. The theory is if you go over it at the correct speed, you shouldn’t feel it too much. But that doesn’t always work.

8.     Ireland has the dubious honour of being home to the first ever recorded road fatality anywhere in the world. In 1869 a scientist called Mary Ward was taking a jaunt on the experimental steam car owned by her cousin, the Earl of Rosse on his estate in Birr Co Offaly – and she fell from the carriage and was crushed.