Phalanx

Phalanx, the ancient Greek formation for heavy infantry, was a series of parallel columns standing close one behind the other, the whole owing to its depth and solidity capable of penetrating any line of troops. The oldest phalanx was the Lacedæmonian or Spartan, in which the soldiers stood four, six, or, more generally, eight deep. The Macedonian phalanx, the latest form, was sixteen men deep. The arms of the men were swords, shields, and long pikes or spears. The heavy-armed phalanx was ordinarily flanked by peltastes or light infantry, similarly formed, who usually fought with javelins and slings.