Rome is about 3.2 times bigger than Denver.

Denver is approximately 396 sq km, while Rome is approximately 1,287 sq km, making Rome 225% larger than Denver.
Tip: This to-scale comparison of Denver vs. Rome uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.