For early 16th-century Europeans, this map was a revelation. It showed a previously unknown island metropolis in the recently discovered Americas — an alien Venice, if you will. However, by the time this first European portrait of the Aztec capital Tenochtitlan was published in 1524, the city, once home to perhaps 200,000 people, was already gone — razed in 1521 by Spanish conquistador Hernán Cortés. In its place, Mexico City would eventually rise. Yet this is more than the ghost map of a recently deceased city. It is a multi-layered document of first contact, evidence of the hybridization of two clashing cultures as well as the dominance of one over the other. Curiously, nobody knows who exactly made this map. The leading theory is that it was based on an indigenous chart of the city. Cortés had obtained from the Aztec emperor Montezuma a map of the coastline, so it seems plausible that a native cartographer provided a cartographic outline of the capital, too.…