Melbourne is about 1.5 times bigger 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 Melbourne (the 27 councils of metropolitan Melbourne, without the Yarra Ranges, Cardinia, Mornington Peninsula and Nillumbik) is approximately 3,915 sq km, making Melbourne 53% larger than Moscow.
Tip: This to-scale comparison of Moscow vs. Melbourne uses the Mercator projection, which distorts the size of regions near the poles.
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