Obelisk of Montecitorio

Obelisco di Montecitorio

Obelisk on Piazza Montecitorio is the former sun-clock, gnomon, that worked perfectly well during the reign of emperor Augustus. The obelisk is an ancient Egyptian, red granite obelisk of Psammetichus II from Heliopolis. It was brought to Rome in 10 BC by Roman emperor Augustus (as a monument dedicated to Egypt's conquest) to be used as the gnomon of the Solarium Augusti and was placed on the Campus Martius. Similar obelisks Egyptians placed at the entrances to the temples of Amen Ra. There is the inscription in Latin written on two sides of the obelisk's base dedicated to Augustus.

Height of the obelisk is approximately 22 m, the weight is about 214 tons. Mathematician Facondius Novus used the obelisk as a hand of a clock and created for Augustus the largest gnomon in the world. Atop the obelisk there was installed a gilded sphere which shadow fell on the surface, a quadrant marked out with bronze letters, with indications of the hours, months, seasons and signs of the zodiac. The meridian placed in the centre of a surface showed the growth and decrease of the day time. During the flood on the Tiber obelisk fell and collapsed into five parts which were later discovered. After reconstruction works the obelisk was installed on Piazza Montecitorio not far away from the original location. It was decided not to restore the gnomon because the whole city quarter would have to be demolished for that purpose. On the spot where the obelisk was discovered Pope Benedict XIV left an inscription in Latin informing us about the discovery and installation of the obelisk in the new location.

Address: Piazza di Montecitorio
Coordinates: 41.900672, 12.478686