[27] Ibid.
A heavy drain on the limited manpower of Marine infantry regiments defending JAMESTOWN was caused by the need to occupy an additional position, an outpost line of resistance (OPLR). This defensive line to the front of the Marine MLR provided additional security against the enemy, but decreased the strength of the regimental reserve battalion, which furnished the OPLR troops. The outposts manned by the Marines consisted of a series of strongpoints built largely around commanding terrain features that screened the 1st Marine Division area. The OPLR across the division front was, on the average, about 2,500 yards forward of the MLR. (See [Map 3].)
To the rear of the main line were two secondary defensive lines, WYOMING and KANSAS. Both had been established before the Marines arrived and both required considerable work, primarily construction of bunkers and weapons emplacements, to meet General Selden’s strict requirement for a strong defensive sector. Work in improving the lines, exercises in rapid battalion tactical deployment by helicopter, and actual manning of the lines were among the many tasks assigned to the division reserve regiment.
MAP 3 K. White
1st MARINE DIVISION SECTOR
30 APRIL 1952
Rear and frontline units alike found that new regulations affected combat operations with the enemy in West Korea. These restrictions were a result of the truce talks that had taken place first at Kaesong and, later, at Panmunjom. In line with agreements reached in October 1951:
Panmunjom was designated as the center of a circular neutral zone of a 1,000 yard radius, and a three mile radius around Munsan and Kaesong was also neutralized, as well as two hundred meters on either side of the Kaesong-Munsan road.[28]
[28] Rees, Korea, p. 295.