Fortress Mode

Hello Chpas just joined the forum as i love the mod, however something is puzzling me, i just can not find how you play Fortress Mode? Am i missing something very obvious ? I cant find it in multilayer or single player? Any help would be greatly appreciated, thankyou.

PS. I hope this is in the correct place.

look for the Red Tide/Blitzkrieg Challenge in Skirmish mode. Map is angoville.

Found it and played it and its excellent, would be cool to be able to play CO-OP against the Computer. :)

Idea is good but i don't know that some of mapper will do 2v2 map for fortress but AFAIK there will be new map for this challange :).

Like a new map ;D