The Gianicolo keeps time for the whole city. Every day at noon a cannon fires one blank round from its slope, so that Rome's church bells have something to agree with. Stand on the terrace just before twelve and you hear the report before you see the smoke. The hill rises west of the Tiber above Trastevere, and stands higher than most of the classic seven without being one of them. Its other business is a defeat. Garibaldi's volunteers fought French troops on this ground to defend a republic that lasted months, and the terrace now carries his statue and an avenue of stone busts of the men who fell beside him.
You climb for the panorama. From the balustrade at Piazzale Garibaldi you look straight out over the roofs of the old centre. Domes and bell towers break the line of terracotta tiles, St Peter's dome stands out to the north, and the Alban Hills close off the horizon behind the city. The view is best when the sun has swung round to the west, and the rooftops shift from ochre to rose while buskers, courting couples and a battered puppet theatre fill the umbrella pines. After dark a slender lighthouse blinks red, white and green above the rooftops.