The Chosin Reservoir was the site of a critical battle in the Korean War. Shortly after the People's Republic of China entered the conflict, the People's Volunteer Army 9th Army infiltrated the northeastern part of North Korea and surprised the US X Corps at the Chosin Reservoir area. A brutal 17 day battle in freezing weather soon followed. In the period between 27 November and 13 December 1950, 30,000 UN troops were encircled by approximately 67,000 Chinese troops. Although Chinese troops managed to surround and outnumber the UN forces, the UN were able to break out of the encirclement while inflicting crippling losses on the Chinese, allowing them to successfully withdraw in good order. The evacuation of the X Corps from the port of Hungnam marked the complete withdrawal of UN troops fr