Sydney is about 15 times bigger than Edinburgh.

Edinburgh (map shows its 30 named neighbourhoods; the area covers the whole city) is approximately 259 sq km, while Sydney (the 30 councils of metropolitan Sydney, without the Blue Mountains, Hawkesbury, Wollondilly and the Central Coast) is approximately 3,810 sq km, making Sydney 1,371% larger than Edinburgh.
Tip: This to-scale comparison of Edinburgh vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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