Ireland is about 18 times bigger 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 Ireland is approximately 70,273 sq km, making Ireland 1,745% larger than Sydney.
Tip: This to-scale comparison of Sydney vs. Ireland uses the Mercator projection, which distorts the size of regions near the poles.
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