Decorated gate of the Royal Palace of Fez, Morocco (© cgst26/Shutterstock)

In Fez, Morocco, the Royal Palace—known as Dar al-Makhzen—has stood as a seat of power since the 13th century, when Morocco's rulers established a fortified royal city around it. Behind its high walls lie gardens, courtyards, mosques and royal residences spread across a vast complex still used by the king today, making it both historic and fully active.