Athens is about 4 times smaller than Houston.

Houston is approximately 1,659 sq km, while Athens (map shows its 34 named neighbourhoods; the area covers the whole city) is approximately 412 sq km, making Athens 24.84% the size of Houston.
Tip: This to-scale comparison of Houston vs. Athens 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.