Sydney is about 1.9 times bigger than Santiago.

Santiago (area of the 32 comunas of Santiago Province) is approximately 2,030 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 88% larger than Santiago.
Tip: This to-scale comparison of Santiago vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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