Sydney is about 7 times smaller than Maryland.

Maryland is approximately 25,314 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 15.05% the size of Maryland.
Tip: This to-scale comparison of Maryland vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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