Santiago is about 1.3 times smaller than Moscow.

Moscow (map shows its 125 districts within the pre-2012 boundary; the area includes New Moscow) is approximately 2,562 sq km, while Santiago (area of the 32 comunas of Santiago Province) is approximately 2,030 sq km, making Santiago 79.26% the size of Moscow.
Tip: This to-scale comparison of Moscow vs. Santiago uses the Mercator projection, which distorts the size of regions near the poles.
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