On one occasion, I visited the front lines in the savagely harsh Salang Pass through the Hindu Kush Mountains.

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Between mountains in the Hindu Kush range lie six, sky-blue lakes.

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But whereas the base in the Korangal was situated about halfway up a mountainside, in a former lumberyard, the one in Kamdesh would sit in a cup within the valley's deepest cleft, ringed by three steep mountains that formed part of the 500-mile-long Hindu Kush mountain range.

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