River Crossing is a 2 player multiplayer map in StarCraft.
The two bases have different defensive options. The top one is close to an arena, forcing enemies to go around. The bottom one is more open, but features a choke point further up. Air support isn't absolutely necessary, but certain resource fields can only be accessed in this manner.
StarCraft Enlarged Map Images. StarCraft Compendium. Accessed on 2008-23-08