City Trees of the Northeastern US

This "map" is of the Northeastern US. It is actually a combination of 4 maps, one of each of the large Northeastern US cities (Washington DC, Philadelphia, New York City and Boston). Each map has been abstracted such that the major rivers running through the city appear as trees, hence "City Trees". I have lived in the Northeastern US for the last 10 years and love each of these 4 cities.