Chapter 11, Verse 1 - Sun Tzu

Sun Tzu said: The art of war recognizes nine varieties of ground: (1) Dispersive ground; (2) facile ground; (3) contentious ground; (4) open ground; (5) ground of intersecting highways; (6) serious ground; (7) difficult ground; (8) hemmed-in ground; (9) desperate ground.
~ from The Art of War, Giles translation ~

Go here to read the introductory post to the verses of The Art of War.