From Gilgit the Karakoram Highway branches away from the Gilgit River and, after following the Hunza River northwards about 100 km reched to Aliabad (2240m). Further, the road climbs, winding up and crossing the Hunza River many times, to reach Pasu (2543m). So I think that altitude at this point is between 2240 to 2243m. Further driving on KKH, one can reach at Sost and Khunjerab Pass (4709m). At the pass the traveler crosses into China having covered a distance of 256 km from Gilgit and 873 km from Islamabad, a journey through one of the most inspiring and desolate regions of the world.