Mussolini commissioned this enormous scale model of Ancient Rome and it took 4 years to build. Surely, much of this is guesswork? [via]
At the Museum of Roman Culture resides a 1:250 recreation of imperial Rome, known as the Plastico di Roma Imperiale, which transports viewers not just through space but time as well. “To commemorate the birth of Augustus (63 BC) two thousand years earlier, Mussolini commissioned a model of Rome as it appeared at the time of Constantine (AD 306-337), when the city had reached its greatest size,” says Encyclopedia Romana. Constructed by Italo Gismondi between 1933 and 1937, then extended and restored in the 1990s, it takes as its basis Rodolfo Lanciani’s 1901 atlas the Forma Urbis Romae.
There are more scale models of cities at io9. Someone should make three-dee scans of all these, to the finest grain!