Seoul is around the same size as Tucson.

Tucson (map shows its 130 named neighbourhoods; the area covers the whole city) is approximately 627 sq km, while Seoul is approximately 605 sq km, making Seoul 96.48% the size of Tucson.
Tip: This to-scale comparison of Tucson vs. Seoul uses the Mercator projection, which distorts the size of regions near the poles.
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