Sun Tzu said (Ch11): The art of war recognizes nine varieties of ground:

1. Dispersive ground When a chieftain is fighting in his own territory, it is dispersive ground. On dispersive ground, therefore, fight not.
2. Facile ground When he has penetrated into hostile territory, but to no great distance, it is facile ground. On facile ground, halt not.
3. Contentious ground Ground the possession of which imports great advantage to either side, is contentious ground. On contentious ground, attack not.
4. Open ground Ground on which each side has liberty of movement is open ground. On open ground, do not try to block the enemy's way.
5. Ground of intersecting highways Ground which forms the key to three contiguous states, so that he who occupies it first has most of the Empire at his command, is a ground of intersecting highways. On the ground of intersecting highways, join hands with your allies.
6. Serious ground When an army has penetrated into the heart of a hostile country, leaving a number of fortified cities in its rear, it is serious ground. On serious ground, gather in plunder.
7. Difficult ground Mountain forests, rugged steeps, marshes and fens--all country that is hard to traverse: this is difficult ground. In difficult ground, keep steadily on the march.
8. Hemmed-in ground Ground which is reached through narrow gorges, and from which we can only retire by tortuous paths, so that a small number of the enemy would suffice to crush a large body of our men: this is hemmed in ground. On hemmed-in ground, resort to stratagem.
9. Desperate ground Ground on which we can only be saved from destruction by fighting without delay, is desperate ground. On desperate ground, fight.

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