Marrakech or Fez for a several day trip from Spain

Tough call. Both are awesome, and each is a bit different. Either would be worthwhile. Marrakech has an extensive medina (old city with twisty little streets filled with market stalls and little shops). It's also got the djema al fema, which is a vast, open public square that is sort of a 200-ring circus, by day filled with all sorts of spectacles, at night it's half filled with spectacles and half filled with food stalls. Marrakech is probably the biggest tourist draw in the country, so it's "easy" to find anything you want/need. Fes is a bigger, older, and less westernized city. The medina is Fes is huge, quite a bit bigger than Marrakech's. Fes is the most intact medieval city in the Arab world, possibly on the planet - in the medina, it really feels like you've gone back in time about 600 years. Any chance you could do both? It's actually quite easy: fly in to one city, spend a couple days, take the train to the other, spend a couple days there, fly out. The trains are quite good. Keep in mind that flights from all over Europe are dirt cheap - makes it easy to use Morocco as a "bridge" to connect two cities in Europe (for example, we flew from Madrid to Marrakech, and from Fes to Paris, where we connected to our flight home. Routings abound, so be creative. Hope that helps.

Both are fantastic. How many days to you have? Fes can be seen in two days, Marrakech has more "sites" to see. In Fes I would recommend taking a medina tour, it's the most amazing old city in Morocco for sure! There is little to see in the new city. In Marrakech you can spend a day in the Djemaa el Fna (the main square) and it's souks (market streets). Then spend a day exploring the historical sites: Bahia Palace, Badi Palace, Si Said Museum, Menara Gardens, Ben Youssef Medersa, cool sites. There are also day trips to the mountains from Marrakech. If you have time to do both go for it! The train is a full day journey though, takes from 7 to 9 hours from Fes to Marrakech. Alternatively you could hire a driver or rent a car if you are flying in and out of one of the cities. The roads are tricky within the cities but the roads between Marrakech and Fes are excellent. Hope you have a great time!

We choose Marrakech! Not enough time to manage both.