Tangier. Just make sure you're going to the Tangier Ville port and not Tangier Med, which is a good way out of town.
Highly recommend visiting the
museum at the Tangier American Legation Institute for Moroccan Studies. That name is a mouthful, but in a nutshell, Morocco was the first country to recognize the United States after we gained independence, and a Legation is similar to a consulate. The Tangier Legation -- which is still owned by the US State Department, but no longer a consular office -- is the only US-owned property on the National Register of Historic Places located outside the United States. It's also the
first diplomatic property the US acquired. There's a beautiful collection of Moroccan art and some fascinating artifacts from American history, like a letter expressing condolences on Lincoln's assassination, and a very funny letter about a couple of lions given to the US ambassador.
Beyond that, (re)watch Casablanca before you go -- Rick's Cafe was actually inspired by Tangier's Hotel El Minzah and during the time of WWII Tangier really was the city populated by an odd international assortment of spies, artists, royalty, people escaping the rest of the world, etc. (Tangier was the first outpost of the OSS -- the CIA's predecessor -- if that tells you anything.)