Erosion

Erosion is an upcoming Forge environment available in Halo 4. This map takes place inside a cavern which has two man-made structures and terrain which naturally slopes down.

Description
This map was announced on a video by Gamespot detailing all three Forge environments in Halo 4.

This map houses two structures by default, of which one is a Grifball court and the other is a pumping station constructed on an overhang. The map features natural ramps and small caves, and offers multi-leveled terrain.

Beyond the second man-made structure, there is small lake over which players can Forge. Furthermore, players can also forge underneath the previosuly mentioned overhang.