Assuming your route will take you through France, Belgium, Germany and Spain, you will need to carry your UK driving licence, proof of ID such as a passport, insurance certificate and V5/C registration document. You will also need to display a 'UK' sticker if your numberplate does not carry this identifier. You will also need to take reflective jackets, a warning triangle, headlamp deflectors if required for your vehicle, a first-aid kit and fire extinguisher. German law also mandates winter or all-season tyres to be fitted in wintry conditions, and given the time of year it is likely that these will be necessary.