There are several documents you must be able to provide to the authorities on request when driving a car in Spain. The title of the documents may depend on the country your vehicle is from but in general the paperwork will be the same for everyone.
You must be able to provide:
- your original full driving licence.
- Proof of identification (Passport, National Identity Card).
- Proof of vehicle ownership. In Spain that would be the permiso de circulacion and the ficha tecnica. If the vehicle is from the UK, for example, you should have the original V5C certificate.
- If you are driving a non-Spanish plated vehicle, then you should also have proof of insurance.
For Spanish registered vehicles the police have a computer system called FIVA (Fichero informativo de Vehiculos Asegurados) where they can check the vehicle is insured. There is no legal requirement to keep the original documents for your car insurance in Spain any longer, for a Spanish registered vehicle.
It would be sensible of course to keep the insurance accident and breakdown recovery numbers in the car as well as the DAA (Declaración Amistosa de Accidente) the Accident Statement.