when should you build a new fortress?

[licker]

Originally Posted by Adept

Lot's of fortifications = lots of income. It takes a while for the fort to pay itself back, but they are the key to making that income curve climb up.

Depends on the kind of fort you are building. If your fort has an admin below 10 you really aren't going to get much extra cash even if you have a high pop place to build it. (forts add admin/2 % to income correct?)

Though generally the forts built in plains have decent admin values...