The Ben-Youssef Madrasa, located in the northern half of the Medina, about a 20min. walk from the Djemaa El Fnaa (excluding the time you'll spend inevitable getting lost), is one of the most incredible and popular sights in the city. It was once a learning center where 175 youths would be taken to learn above all the Koran, but also philosophy, astronomy, medicine, and other worthy pursuits. These days, it's most famous for being a sterling example of Moorish architecture and design, as well as a generally lovely place that evokes a feeling of peace and inner quiet.
The structure is based around a central courtyard whose decoration and amazing conservation rival that of the Alhambra in Spain, one of the wonders of the world. The tri-color Moorish tile-work, reflecting pool, and Moorish arches are simply stunning when the bright African sun illuminates it all. The flank buildings are occupied by dormitories and rooms of unknown purpose which, while typically spartan in their decoration, offer amazing views of the courtyard and conceal some surprising touches like arched windows, balconies, and intricate woodwork where you least expect them.