Houston is about 4 times bigger than Athens.

Athens (map shows its 34 named neighbourhoods; the area covers the whole city) is approximately 412 sq km, while Houston is approximately 1,659 sq km, making Houston 303% larger than Athens.
Tip: This to-scale comparison of Athens vs. Houston 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.