New York City is about 7 times bigger than Ulm.

Ulm (map shows its 55 named neighbourhoods; the area covers the whole city) is approximately 119 sq km, while New York City (including all five boroughs: Manhattan, Brooklyn, Queens, The Bronx, and Staten Island) is approximately 781 sq km, making New York City 558% larger than Ulm.
Tip: This to-scale comparison of Ulm vs. New York City uses the Mercator projection, which distorts the size of regions near the poles.
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