I'm still in the process of finishing the regional map for my campaign, but thinking ahead a bit I'm wondering how BIG some of the cities should be. There are beautiful maps on here and a lot of discussion about mapping technique, but I haven't seen anything about population and city size with the exception of this post by terminal.

Assuming the 180 people/sq.mi. mentioned in there... That would mean that a 10,000 person city (which is really big by D&D standards) would span apx. an 8 mile diameter area. What does an 8 sq. mile city look like?

I'm posting a few examples from the Cartographer's Choice section as examples, not as my work... hope this is okay.
The City of Castran - How many people would this city house? It's freakin enormous so... is this a 10,000 person city?

Haibianr - This one's a little smaller. Maybe 2,000?

Trying to get a feel for how large of a map I will need for a few of the locations my players will be exploring. I hope you're able to understand what I'm trying to figure out. Thanks for any input!