TOP  Strategy Phase  Infrastructure

Upgrade 

Increase the HP of a base. Higher HP gives an advantage during castle defense.
Upgrading can take several months.

Base Info

Repair 

HP lost in castle defense will be recovered completely over the course of 1 month. It will require an amount of gold based on the amount of HP that needs to be recovered.
HP will recover gradually each month even without it, so only use Repair when there is a need for speed.

Construct 

Build another base. You cannot construct in counties that already have a facility or a castle in it, or with extremely rough terrain. Also, counties neighboring castles are not available either.
The type of base built is decided by the county. Flatland castles are cheaper and can be built quicker. Mountain castles have ore HP.
Additionally, if there isn't a trade zone in the county, a castle trade zone will be created.

Trade Zones

Raze 

Raze a base that you have constructed. You cannot raze a base that was there from the start.
After razing a base, the officers that were stationed there will go to the nearest base. Any Castle Trade Zones will also be removed.