Sydney is about 71 times smaller than Colorado.

Colorado is approximately 268,627 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 1.42% the size of Colorado.
Tip: This to-scale comparison of Colorado vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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