Visviri Pass
Paso Visviri is an international high mountain pass at an elevation of 4.095m (13,435ft) above the sea level, located on the border of Chile and Bolivia.
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The road over the pass is gravel. The climb is simply terrible, with a notorius lack of oxygen that tests the organisms and a high degree of steepness. Most people feel altitude sickness at around 2,500-2,800 meters. This track can get very muddy and slippery after rain making it challenging to get through. The border is open from 8 am to 10pm.
Pic: Octavio Aldea