The following gives information for visitors as well as residents.  However, there is far too much to include here and anyone driving any distances in Spain should consider obtaining the book, Motoring in Spain by Brian J Deller.

If you wish to see as much as possible of Spain then having your own car is certainly the best method of transport, even if it may take you a couple of days to feel confident about driving on the opposite side of the road. As an EU citizen and a tourist, to drive a foreign registered vehicle in Spain you must have with you, and you can be fined for not obeying the following: -

4. Approved reflective jackets that must be worn by all outside the car at anytime, day or night, outside the vehicle at the side of any highway not in an urban (street lights?) area. The jackets must be kept inside the car so they can be put on before getting out and also must be visible from outside the car. The pocket in the back of the front seat is a good place.  The jackets are inexpensive and can be bought at most supermarkets if you do not have them already

Remember that your “tourist status” in a foreign country usually applies for only three months as far as insurance is concerned, so for any longer periods, do not forget to discuss this with your broker.  

The roads in Spain vary from very poor to very good, the latter especially since Spain joined the EU and has benefited from the funding from other countries over the last 20 years. The main connecting roads are generally excellent. Roads are classified thus, and they can be easily clarified on a road map.

The Law for pedestrian crossings until recently is not as strict as in for example, the UK where a driver is always at fault if the vehicle hits a pedestrian on the crossing.  You must step onto the crossing, remembering to look LEFT, and show the palm of your hand to any approaching vehicles.  Previously, they still did not have to stop, but a new Law involving penalty points means that the drivers can be penalized now for not stopping. Many tourists are injured, some killed each year, for only looking right when crossing the road. 

You may NOT overtake on the right (inside lanes) on the highways unless there is a slip road or another road indicated and you are taking it. I know this is the same elsewhere in the World where bad drivers insist on cruising in the middle lanes.

A FEW BASIC RULES
Give way to traffic from the left unless otherwise signed, especially on roundabouts. Do not pull into the middle of the road to turn left if there is a solid line in the road. There are often special lanes for this, signposted cambio de sentido (change of direction), especially on the autovias. All people in the car must wear seatbelts if fitted, and children must be in specially approved (EU) seats situated only in the rear due to possible injury by front airbags in the event of a crash. Do not drink and drive - the limits are about half those in the UK and the penalties very high including losing your licence on the spot, boosted by the new “rapid justice” Courts, as are heavy on-the-spot fines for traffic offences. You will not be allowed to leave the area until you have paid any fine or appeared in Court, including spending time in the cells if you cannot pay in cash. 

Parking
As a general rule you may not park in Spain where the pavement curb is painted yellow or where a no parking sign is displayed. In major cities and now even the pueblos, non-metered on-street parking is difficult to find but in some areas, there are parking spaces marked in blue for which you should purchase a ticket from a nearby machine on the pavement usually topped with a blue and white “P” sign, or from an attendant. These spaces are usually for about two hours maximum. Penalties for parking infringements vary from town to town and can be heavy.