Half-Life DM MetalBox Map

and sniper nests. This map can reasonably accomodate up to 20 players. Anything more, and it gets a little crowded. :)
dm_metalbox is a killbox-inspired map thats split into two hemispheres -- a Combine side, and a Rebel side. There are tons of catwalks to fight like hell on, lots of hiding places, comping places,