The salt pans set just outside Marsalforn are the island's most spectacular system. The northern coast of Gozo was particularly suited to salt production, as its area of flat limestone could be cut into by hand. Seawater ran into the shallow basins and the wind and sun did the rest; the salt pans on Gozo apparently date from Roman times. Small caverns were cut into the rock to store the salt. The Knights were in charge of salt harvesting and fined anyone who produced salt without permission. Nowdays the salt is still harvested between May and September, but only for local use. The sea and wind can be wild here, as it hammers the surrounding cliffs into sculptural shapes.