There are hundreds of signs and you cannot memorise them all. You do not need to. Irish signs follow a system, and once you know it you can read a sign you have never seen before.
Shape and colour
| What you see | What it does |
|---|---|
| Amber diamond | Warning — a hazard is ahead |
| Orange diamond | Warning at roadworks — temporary |
| Red circle | Prohibition — you must not |
| Blue circle | Mandatory — you must |
| Octagon | Stop, and nothing else |
| Inverted triangle | Yield |
| Blue rectangle | Information |
Red prohibits, blue compels. Getting that pair straight answers a large share of the sign questions on the test.
The amber diamond catches people out
Most of Europe and the UK use a red triangle for warnings. Ireland uses an amber diamond. If you learned to drive abroad, this is the single most important difference to fix.
Direction signs: colour tells you the road class
| Colour | Road |
|---|---|
| Blue | Motorway |
| Green | National roads (N-numbers) |
| White with black text | Regional and local roads |
| Brown | Tourist and heritage attractions |
This is more useful than it looks: the colour tells you what kind of road you are being sent onto, and therefore what its default speed limit is.
One extra rule worth knowing: a route number shown in a blue box on a green sign means that road upgrades to motorway standard further along.