In the area delimited by the Arch of Constantine, the east slopes of the Palatine and the remains of the base built by Hadrian for the Colossus, colonnades were recently brought to light that were designed and built by Nero around the artificial lake of his Domus Aurea. They served as a link between the vestibule of his palace on the summit of the Velia (where there is now the Temple of Venus and Rome) and the valley below. A few remains can now be seen between the Flavian Amphitheater and the circular base of the monumental fountain of the Flavian era that the ancients called Meta Sudans.
The Meta had a characteristic conic shape similar to the meta of a circus and was called sudans because of the water that spouted from it. It was located at the point where four or five Augustan regions — the II, III, IV, and X, and perhaps the I – and as many major streets converged.
The fountain consisted of a cone (17 meters tall, with a diameter of 7 meters) and a large circular tub with a diameter of 16 meters. Its original appearance can be reconstructed from coins ofthe period, which portray the niches of the base and the floral element on the tip of the cone.
What remained of the monument, which is still clearly visible in photographs from the beginning of the century, was demolished, together with the nearby base of the Colossus, when Via dei Trionfi and Via dell ‘Impero were built in 1933.