Driving to Morocco

@aviator1 She will NOT be able to transit without a transit visa which you need to get from French consulate as it will your first point of entry to Schengen area ( EU ). You will probably need to get another transit visa on the way back from the Spanish consulate as it will be your first point of entry to Schengen area. I hope that this helps.

@Said Idouarab

Hi, thank you for your reply! I thought this may be the case. We live in the north of England and would have loved to be able to drive to Meknes next summer when we visit again.

Do you know if the process of obtaining a visa to drive through is simple or difficult?

@aviator1 as uk resident ( but nor British ) your wife should be able to apply for a transit visa at the French consulate or embassy in the uk. But the visa will only be valid to from here to Morocco. Link below.

https://www.schengenvisainfo.com/france/visa/uk/

unfortunately your will need to get another visa on the way back as your entry point to the EU will be Spain. You can not use a visa obtained in the French embassy to enter Spain as a fist point of entry. Link below.

https://www.schengenvisainfo.com/spain/visa/uk/

I hope that this helps.