Driving with Dogs has comprehensive listings of vet clinics throughout France. We've focused on vet clinics where some English is spoken, and that are convenient for compulsory tapeworm treatments - close to the main autoroutes through France from Spain in the west, and from Germany, Italy, Austria and beyond to the east.
Dogs returning to the UK after a holiday in France all need to have tapeworm treatment before they will be allowed back into the UK. There's a fixed time period for the treatment, and you may need to find a vet outside the area where you've been staying - or if you're just driving through France to cross the Channel. Current rules state that 'The treatment must have been given within 1 and 5 days (between 24 and 120 hours) before you’re scheduled to enter the UK'.
To see the France vet clinic listings, first sign in to your Premium acount and then click on Vets in France from the home page, or just click France Vets to go straight there.
Check out the current Pet Passport regulations on: https://www.gov.uk/take-pet-abroad/tapeworm-treatment-dogs and be aware that after Brexit everything will change.