Information: The City walls on the map have been represented in 4 sections, with border lines in different colors. The red line stands for the Etruscan Walls, the yellow line represents the hidden Etruscan Walls, the blue line the Medieval and walls of the following epochs, the light blue lines are for the hidden Medieval and the following eepochs walls. This delimitation is to be considered reliable in the visible sections of the walls and approximative in the hidden ones.