Wooden and stone forts.
They could be very usefull to hold strategic positions all over the map.
In a mod of "one year-one turn"or even"one year-two turns" forts of this kind could give an essence of realism.A good idea could be that stone forts would not disapear even they are without garison,even more...damaged.
A very powerfool and valueable price for any offencive player.
An expencive but necessary tool for any defencive one.
Costs and time of constract under discution.I still think that castles as the M2TW sould continue to exist.A fort must be simply a power point on the map but not a power demostrading point like castles...