The Wakhjir Pass, also spelled Vakhjir Pass, is a mountain pass in the Hindu Kush or Pamirs at the eastern end of the Wakhan Corridor, the only potentially navigable pass between Afghanistan and China in the modern era. It links Wakhan in Afghanistan with the Tashkurgan Tajik Autonomous County in Xinjiang, China, at an altitude of 4,923 metres (16,152 ft), but the pass is not an official border crossing point. With a difference of 3.5 hours, the border has the sharpest official change of clocks of any international frontier (UTC+4:30 in Afghanistan to UTC+8, in China). China refers to the pass as South Wakhjir Pass (Chinese: 南瓦根基达坂), as there is a northern pass on the Chinese side.