Fontana delle Tartarughe first water flowing to a reservoir near the present Trevi Fountain. Della Porta and the city of Rome made a plan to build eighteen new fountains connected to the new aqueduct. He began in 1572 with the fountain in Piazza del Popolo, then built the two famous fountains of Piazza Navona (1574–1578), and the fountain in Piazza della Rotonda in front of the Pantheon (1575). + In the original plan of 1570 a new fountain was to have been placed near the Theater of Marcellus in the Piazza Giudea, the site of a market in the Roman Ghetto. One of
Piazza della Rotonda the fountain in the Piazza della Rotonda was authorized on September 25, together with a fountain for Piazza Colonna, and two more for Piazza Navona; the fountain for the Rotonda, completed in 1575, was of a chalice-type design, around 3.5 to 4 meters in height, and fed with the Vergine water through a terracotta conduit. Della Porta designed the fountain, and Leonardo Sormani executed it. Due to the slope of the piazza, the fountain is approached by five steps on the south side, and only two on the north. Under the pontificate of Alexander VII Chigi, projects were set afoot