The Biafo Glacier is a 67 km (42 mi) long glacier in the Karakoram Mountains of Gilgit Baltistan, Pakistan which meets the 49 km (30 mi) long Hispar Glacier at an altitude of 5,128 m (16,824 ft) at Hispar La (Pass) to create the world's longest glacial system outside the polar regions. This highway of ice connects two ancient mountain kingdoms, Nagar (immediately south of Hunza) in the west with Baltistan in the east.