In the center of the old town of Nyons, the church and the monastery Saint-Césaire are located on a site certainly occupied since antiquity. Above, the Forts district, with its thirteenth-century towers and its walls, is a secular neighbourhood. To the east and west, the city then developed around the Place des Arcades and a street that led to the Alps. The city remained in the walls until the eighteenth and it was not until the twentieth century that it spread in the lowland.