This multiplayer map includes a relatively limited farming area for both keeps. Each keep has individual access to its own scattered resources. However there are sources of stone and a huge amount of iron that both keeps have equal access to.
Designers observations: If you allow your oponent to gain uncontested contol of the "Iron Mountain" for any significant period of time you may find that you will not be able to produce the necessary units to defeat him on the battlefield.
Please see the in game story for the background on this map.