It includes certain things and excludes others: it separates an interior from an exterior space. It produces a small region where the urban pressure of Mexico City is both absorbed and provisionally suspended. Outside, the walls provide 120 sqm of total exhibition surface for the festival purposes. But they can also be painted, used to hold temporary structures, covered with advertisment, vandalized. Inside, a silent “fragment of desert” holds the memory of the origin of the city. It doesn’t suggest any specific activity, nor tries to forsee them. Its gentle slope is generous enough to accept the unpredictable.