New Haven is about 7 times smaller than Rotterdam.

Rotterdam (map shows its 22 named neighbourhoods; the area covers the whole city) is approximately 319 sq km, while New Haven is approximately 48 sq km, making New Haven 15.16% the size of Rotterdam.
Tip: This to-scale comparison of Rotterdam vs. New Haven uses the Mercator projection, which distorts the size of regions near the poles.
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