Porirua is around the same size as Potsdam.

Potsdam is approximately 188 sq km, while Porirua is approximately 182 sq km, making Porirua 96.88% the size of Potsdam.
Tip: This to-scale comparison of Potsdam vs. Porirua uses the Mercator projection, which distorts the size of regions near the poles.
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