Korengal Valley is among the deadliest pieces of terrain in the world for U.S forces. The six-mile long strategic passage is located in northeastern Afghanistan surrounded by treacherous mountain ridges, which are held desperately by the Taleban and al-Qaeda. Nearly one-fifth of all combat in Afghanistan occurs in this valley, and nearly three-quarters of all the bombs dropped by NATO planes target the surrounding area. The Valley is the first leg of a former mujahideen smuggling route that was used to bring in men and weapons from Pakistan during the 1980s
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