Antwerp is about 4 times smaller than Calgary.

Calgary (map shows its 242 named neighbourhoods; the area covers the whole city) is approximately 826 sq km, while Antwerp (map shows its 62 named neighbourhoods; the area covers the whole city) is approximately 208 sq km, making Antwerp 25.22% the size of Calgary.
Tip: This to-scale comparison of Calgary vs. Antwerp uses the Mercator projection, which distorts the size of regions near the poles.
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