Melbourne is about 16 times bigger than Frankfurt.

Frankfurt is approximately 248 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 1,477% larger than Frankfurt.
Tip: This to-scale comparison of Frankfurt vs. Melbourne uses the Mercator projection, which distorts the size of regions near the poles.
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