Rome is about 66,703 times bigger than Colosseum.

Colosseum is approximately 0.019 km² (0.0075 sq mi), while Rome is approximately 1,287 sq km, making Rome 6,670,159% larger than Colosseum.
Tip: This to-scale comparison of Colosseum vs. Rome uses the Mercator projection, which distorts the size of regions near the poles.
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