西班牙大方阵（Tercio），这是由西班牙人所研究出来的战斗队形，由贡萨洛·费尔南德斯·科尔多瓦所创立。部队会面对敌人排成横向的长方形，并且在长方形的4个角落配置方阵，中央方阵横向为100列，纵向则为12至15列，外缘2列是大型火绳枪兵，而中央则是以西班牙长柄枪兵所构成的队形。位于4个角落的横5行纵6列小方阵，都是由大型火绳枪兵所构成。一个长形方阵约有3000名士兵，只要士兵数量足够就会以好几个长形方阵的状况来布阵。虽然是可以朝任何方向发射子弹的无敌队形，不过朝特定方向的火力却也因此降低不少，另外排列这个队形需要花上很多时间，所以机动力也很差。

A tercio (Spanish pronunciation: [ˈterθjo] "third") or tercio español ("Spanish third") was a Spanish infantry organization during the time Habsburg Spain dominated Europe in the Early Modern era.

The tercio was an administrative unit with command of up to 3000 soldiers, subdivided originally into ten, later twelve compañías, made up of pikemen, swordsmen and arquebusiers or musketeers. These companies were deployed in battle and were further subdivided into units of thirty soldiers. These smaller units could be deployed individually or brought together to form what were sometimes called Spanish squares. These powerful infantry squares were also much used by other European powers, especially the Imperial Army of the Holy Roman Empire.