Other than that, Casablanca is like any other European city: the streets (mostly) have signs, and passersby are extremely helpful in French or Arabic and, more rarely, Spanish or English. The Medina can be hard to navigate, but it’s so small that no matter how blindly you wander into it, you’re never more than ten minutes from an exit.
King Hassan II Mosque (map). The largest mosque in Morocco and the third largest in the world. The 210 m high minaret is the tallest in the world. It opened in 1993, after six years of construction. It is one of the two main mosques in Morocco open to non-Muslims. Beautiful interior complete with water features, a roof that opens to the sky, a huge hammam in the basement (not in use), and beautiful tile work.
Old Medina (map). If you are in town it’s worth a visit, but it is nothing compared to the glories of *Fes or Marrakesh.
Casablanca is one of the least interesting places to shop in Morocco. Around the old Medina it’s easy to find places selling traditional Moroccan goods, such as tagines, pottery, leather goods, hookahs and a whole spectrum of knicknacks, but it’s all for the tourists. Much better to wait until you’re in Fes and can bargain with someone who sells things to both Moroccans and tourists.
Almost all of the things to see in Casablanca are in the north of the city; very few maps even show the southern end of this sprawling metropolis. Common sense will alleviate 99% of problems; try to look as little like a tourist as possible, do not flash large quantities of cash, and so on.