The fourth palace gate, to the west, became the most important from the 16C when the Venetian district grew in size. It was then the meeting point between the palace town and the new district. Swamped by later constructions, its double-entrance security system remains and it gives an idea of the immensity of the palace's walls. The guards lived above the outer door. In the Middle Ages, it was the only door, with that of the port, to remain open.