The Macedonian Phalanx is a military formation of armored pikemen that first saw widespread use in the armies of Alexander the Great, as well as in the Diadochi kingdoms following the breakup of his empire. While the armor worn by phalangites or pikemen varied greatly throughout classical antiquity, their main weapon was typically a sarissa or xyston 21 feet in length. Phalangites marched in formations of between eighty and three hundred men in rows four to twelve men deep and arranged in such a manner as to present a wall of spearpoints toward the enemy.