Hypercities is a Google Maps mashup of historical maps of some of the world's cities. Hypercities allows the user to navigate a selection of historical maps using the familiar Google Maps navigation tools.
It is a year since we first featured Hypercities on Google Maps Mania. In that year Hypercities has added Lima, Ollantaytambo, Rome, Tehran, Saigon, Shanghai, Seoul, Tokyo and London to the original list of cities of Berlin, New York, Los Angeles and Tel Aviv.
If you navigate to one of the mapped cities you can view the historical maps that Hypercities has to view. For example, in London you can view John Snow's famous cholera map superimposed on Broadgate Street.