Moscow is about 3.1 times bigger than Kansas City.

Kansas City (map shows its 145 named neighbourhoods; the area covers the whole city) is approximately 815 sq km, while Moscow (map shows its 125 districts within the pre-2012 boundary; the area includes New Moscow) is approximately 2,562 sq km, making Moscow 214% larger than Kansas City.
Tip: This to-scale comparison of Kansas City vs. Moscow uses the Mercator projection, which distorts the size of regions near the poles.
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