Antwerp is around the same size as Riverside.

Riverside is approximately 210 sq km, while Antwerp (map shows its 62 named neighbourhoods; the area covers the whole city) is approximately 208 sq km, making Antwerp 99.07% the size of Riverside.
Tip: This to-scale comparison of Riverside vs. Antwerp uses the Mercator projection, which distorts the size of regions near the poles.
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