Reading around Dragon'sfoot, a poster submitted a two page write-up for a campaign area. (Link to thread here.) The submission was a write up for the Principality of Kedmere.

This is a concise and easily adaptable summary of a campaign area, complete with a map. Major cities and towns get a good description along with population, leaders, and other important details.

It is easy to imagine that providing more detail to areas within Kedmere could be done with a similar two page write up. For example, a writeup on Belmord complete with city map, building details, etc.

All in all this is an excellent way of presenting broad areas of the campaign world. I can get lost in centuries of history, but this straight-to-the-point presentation is 'just right'.