plaza precedent studies:
Piazza Navona
Architect: Gian Lorenzo Bernini Location: Rome, Italy Date: 1651
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This is the Piazza Navona in present day. In the center are the three famous fountains. You can also see the structures resemble the full shape of the Stadium of Domitian that was in place before the Piazza Navona.
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This is an overlay of the Stadium of Domitian which was the structure that was built over by the Piazza Navona. In fact, some of the base structure of the stadium was used for the new structures that were built surrounding the plaza. This is why as a mass they look so similar.
This diagram illustrates in red, the pedestrian distribution across the plaza as well was the various entry points to the plaza. The blue illustrates the three fountains as well as the approximate area would get flooded for the Pamphilj family celebrations.