Any special requirements in driving from Spain to France?

I have no administrative advices, but just some suggestions for great sightseeings along the road:

• avoid the highway between Barcelona and Perpignan: prefer the coastal route where the Pyrénées meet the sea. Landscapes are wonderful and you can stop at Figueres and Cadaqués, the home region of Salvador Dalí, then at Banyuls and Collioure for wine and anchovies.

• Don't forget Andorra and Cerdagne, a region where the borders are more blurry than what is depicted on maps - people soul is more catalan than french or spanish. Odeillo and Mont-Louis are worth visiting.

• The whole region is full of cathar castles worth visiting. The most famous is Montségur. If you don't mind going north, make a stop at Carcassonne.

If your vehicle has a European style licence plate (i.e. EU flag on the left hand side and country code, e.g. E for Spain), you can legally drive all over EU. Some countries (Ireland) always have an EU style plate, some countries (UK) do not always have this style.

Car insurance should cover you all over the EU (normal car insurance anyway, I don't know about hire cars)

Ask/Tell your car hire company.

The Pyreenes are very nice. Try to take some scenic roads, rather than the main motorway.