Jianmen Pass (Jianmen Guan, 剑门关) is a key 50-meter wide mountain pass between Shaanxi and Sichuan. The ROC fortified the pass with bunkers during the Civil War in preparation for a PRC attack. The PRC captured nearby Guangyuan on December 14, 1949. The PRC's 540th Regiment (of 180th Division, 60th Army, 18th Army Group) was assigned to take the pass, which it reached after a 40 km three day forced march through the mountains. The initial attack destroyed a company of the defending ROC 55th Division. Two of the 540th Regiment's battalions approached under the cover of darkness to 50 meters of the pass 10:00 PM; the remaining battalion outflanked the defenses by moving through the mountains. The attackers crossed a final ravine with a log and overwhelmed the defenders. The PRC captured 300 prisoners.[citation needed]
The ROC retreated and abandoned Jiange in the afternoon of December 18, 1949. The way was cleared for the PRC to push deeper into Sichuan.[citation needed]
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