Lisbon is about 8 times smaller than New York City.

New York City (including all five boroughs: Manhattan, Brooklyn, Queens, The Bronx, and Staten Island) is approximately 781 sq km, while Lisbon (map shows its 24 named neighbourhoods; the area covers the whole city) is approximately 100 sq km, making Lisbon 12.81% the size of New York City.
Tip: This to-scale comparison of New York City vs. Lisbon uses the Mercator projection, which distorts the size of regions near the poles.
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