Here are some comparisons I like to use that really put things in perspective, particlarly for Europeans:

1. The Greater Houston Metro Area is larger than Wales;

2. Greater Houston has fewer people than London but is almost twenty times the area;

3. IIRC if liad out the Greater Houston area over England it would stretch from London to Birmingham;

4. Greater Houston is, in fact, larger than several states including New Jersey;

5. Greater Houston is more than half the size of Switzerland.