This is the eighth level of the game, and is also the second level of chapter two. He escapes from a science-oriented base to a military oriented one, complete with alien tanks and aliens dressed in army garb.
Throughout the levels are tanks that do not directly attack Duke, but constantly bombards a cetain area. This level also includes a lot of back-tracing in order to continue through the level. Although the sole movable enemy, the trenchmen are one of the trickiest enemies, whose attacks range from rolling the player as well as firing their guns.
The exit for this level is at the end of an underground tunnel which can be accessed via a locked hatch. Duke must reach to the other side of the base in order to push the button which opens it. The tunnel would also contain a button for the next hatch, and it will repeat the actions until Duke manages to enter the last tunnel.