Using open data from PLUTO and OpenStreetMap, Lu created this color-coded map of 1,053,713 buildings in the city in just two days. Visit the map itself at bdon.org, and you can zoom down into neighborhoods and specific streets.
While the visualization is impressive, it's not altogether accurate, Liu told The Atlantic Cities in September -- one viewer said to Liu, "I'm looking at Union Square and a lot of this data is incorrect."
Liu told The Atlantic Cities that NYC acknowledged errors in the data, citing the date of the Museum of Natural History. The city lists it as 1995, but "the original built date is far before that," he said.