Tagged with the ominous sounding name “Yaban-san” by Koreans, this hill resembles a huge molar whose roots rise from the MSR west of Chindong-ni and lead to a tremendous mass about 2,000 yards north of the road. There the ground climbs sharply, culminating in a peak 1,100 feet high. Beyond, a long saddle extends a few thousand yards northwest, connecting 342 with a height of almost 2,000 feet. The latter was a stronghold of NKPA 6th Division elements, making a determined bid to carry 342 and cut the MSR. Assigned the mission of making the Brigade’s first ground contact was young Lieutenant Cahill of Company G. His 1st Platoon was reinforced with a machinegun squad and SCR-300 operator before he led it from 3/5’s perimeter. Moving westward on the MSR, the platoon reached Michaelis’ CP, located near the bridges south of Hill 99. Cahill was told that he would be met by a guide at a road junction 700 yards farther down the MSR. From this point the platoon followed a soldier who escorted Cahill to the CP of the 2d Battalion, 5th RCT. This headquarters was situated just north of the road, on the tip of 342’s eastern “root,” 1 of the 2 long ridges leading to the hill itself. The Marine officer was told to relieve the Army company on the summit and hold the hill with his platoon. Following a quick briefing, Cahill and the guide led the column northward from the CP, skirting the western base of the ridge. A few hundred yards along the way, the guide discovered that he had miscalculated in the darkness. More time was lost while the platoon descended to resume the correct route. As the men threaded their way along the unseen trail, a few enemy artillery shells burst nearby. The column reached the end of the valley separating the two long spurs of 342, and a volley of rifle fire cracked in the darkness. Two of Cahill’s Marines were painfully wounded. Since the column was still in friendly territory, the guide advised Cahill not to climb 342 until dawn shed light on the mystery. It was then 0500, 7 August, and the Marine platoon had marched 3 miles from its original position. Shortly after first light, it was discovered that soldiers of the 2d Battalion, 5th RCT, had fired on the Marines, not realizing that friendly units were moving within the area. As the sun rose in a cloudless sky, Cahill took the lead. First, he climbed the high ground joining 342 with its eastern spur, then crossed over and continued toward the peak from a southeasterly direction. [Illustration: CHINDONG-NI AREA 6–9 AUG. ’50 SHOWING 1st PROV. MAR. BRIGADE’S DISPOSITION, BLOCKING ACTION, & LOCAL ATTACKS]