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Hiking in Bulgaria. Hikers at a base camp by the Sinanitsa Peak in Pirin National Park and Reserve, Pirin Mountain, Bulgaria, Balkans, Europe Stock Photo - Alamy
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Natural hot springs at the base camp in the region of Landmannalaugar, Iceland, Europe Stock Photo - Alamy
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File:Romanian artillery piece in front of the “permanent” base camp near Mihail Kogalniceanu Air Base in southeast Romania.jpg - Wikimedia Commons
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