Rockville is around the same size as Gisborne.

Gisborne (map shows its 10 named neighbourhoods; the area covers the whole city) is approximately 38 sq km, while Rockville (map shows its 87 named neighbourhoods; the area covers the whole city) is approximately 35 sq km, making Rockville 91.46% the size of Gisborne.
Tip: This to-scale comparison of Gisborne vs. Rockville uses the Mercator projection, which distorts the size of regions near the poles.
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