Cape Town is about 1.6 times smaller than Sydney.

Sydney (the 30 councils of metropolitan Sydney, without the Blue Mountains, Hawkesbury, Wollondilly and the Central Coast) is approximately 3,810 sq km, while Cape Town is approximately 2,455 sq km, making Cape Town 64.43% the size of Sydney.
Tip: This to-scale comparison of Sydney vs. Cape Town uses the Mercator projection, which distorts the size of regions near the poles.
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