MCRP 12-10B.1, page 84

(2) Main Battle Area. The decisive battle is fought in the main battle area. However, the commander may deploy units on the forward edges of the city or in battle positions in depth. The defensive scheme should include forces to defend along the flanks. The commander normally employs security forces to the front to provide early warning and to deny the enemy intelligence on the unit’s defensive dispositions (counterreconnaissance) (Figure 3-6). (a) The size and location of battle positions depend on METT-T and the type of defense prepared. A sophisticated defense will often include a combination of both position and mobile defense but will always be planned in depth. (b) A unit assigned battle positions on the forward edge of a city or town should: Provide early warning of the enemy’s advance Engage the enemy at long range Deceive the enemy as to the true location of the defense. Figure 3-6. Main Battle Area (c) The defender employs all available fires to destroy and suppress the direct-fire weapons that support the ground attack. Depending on the concept of operations, Military Operations on Urbanized Terrain 3-13