From and To Fez:
You have multiple options to come to Fez and it will depend on your city of departure as well as how much time you want to spend in Morocco. The is multiple of airlines, flying directly to Fes or to Casablanca, Royal Air Maroc and Jet4u can be absolutely recommended aside of the know European airlines. (Jet4u is a low cost airline like easyjet but belongs to the German TUI group). Flights start at 250EUR from most European cities to Casablanca.

General Connections:
By plane
    ▪    Royal Air Maroc offers daily flights to Casablanca from Frankfurt, Geneva, London-Gatwick and Paris-Orly
    ▪    Jet4You flies from Paris-Orly to Fez directly
    ▪    Ryanair offers flights from:
         Barcelona, Madrid, Seville, Alicante, Frankfurt, Dusseldorf, Charleroi (Brussels), Marseille and London Stansted to Fez

    ▪    Transavia flies from Paris-Orly to Fez.
    ▪    Easy Jet flies from Paris-CDG to Fez

Option1:
Flights from Europe to Fez directly or via Casablanca airport. This might be the easiest option, but there is only one flight per day from Casablanca to Fez. (Flights from Casa to Fez daily with Royal Air Maroc for around 35EUR one way)

Option2:
Flight from Europe to Casablanca airport and take the route with a hire car to Fez. The distance is only around 280km (a bit more than 3h) on a newly finished highway, easy to find and easy to drive. The benefit of this option is the multiple flights a day from most European cities to Casablanca and the potentially cheaper flight costs.

Option3:
Flight from Europe to Casablanca airport and take the train directly from Casablanca airport to Fez.