Colosseum is about 66,703 times smaller than Rome.

Rome is approximately 1,287 sq km, while Colosseum is approximately 0.019 km² (0.0075 sq mi), making Colosseum 0.0% the size of Rome.
Tip: This to-scale comparison of Rome vs. Colosseum uses the Mercator projection, which distorts the size of regions near the poles.
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