Colonization: It costs 2/2 to start colonizing a region. This region will take 5 turns to become fruitfull. It you leave it unprotected you risk losing all progress.
Castles: Castles cost 2/2 to build. They will be finished on the fifth turn after construction is ordered. A castle takes 1 turn to siege unless it has the siege trait.
If a castle is started on Turn 1; it will be complete upon the Income phase of Turn 5.
A castle can either be a Gold((+1/0)) a Food ((0/+1)) or a siege((requires two turns to siege over one))
Ports: Ports cost 2/0 and take 2 turns to build. They allow your troops to travel over water. These are sackable if an enemy force invades the territory it is on.
Trading Post: If a player owns a port within the Vale they get an automatic Trading post which allows them to trade 2 of one resource for 1 of the other resource.
Farms: Avalible to those with land within the Riverlands; costs 0/2 and takes 2 turn to build. Gives the region it is on 0/+1. Farms are burnable if the land is raided and can remain intact for use by the conquering player.
Mine: Avalible to those with land within the Westernlands; costs 2/0 and takes 2 turns to build. Gives the region it is on +1/0. Mines are destructable if the land is raided and can remain intact for use by the conquering player.