Melbourne is about 11 times bigger than Atlanta.

Atlanta (map shows its 114 named neighbourhoods; the area covers the whole city) is approximately 350 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 1,017% larger than Atlanta.
Tip: This to-scale comparison of Atlanta vs. Melbourne uses the Mercator projection, which distorts the size of regions near the poles.
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