Sust or Sost in Hunza Valley, North Pakistan

 Sost or Sust is a village in Gojal, Upper Hunza, Gilgit-Baltistan, Pakistan. It's the last town in Pakistan on the Karakoram Highway in front of the Chinese border. It is 2,800 metres above sea level. The city is an important highway point for both passenger and freight transport, as all traffic crossing the border between Pakistan and China passes through the city; Pakistani immigration and customs departments are located here. Pakistan and China have opened the border for trade and tourism in Khunjerab.

The Silk Route Dry Port began its business operations at Port Sost (Upper Hunza) near Khunjarab Pass Gilgit-Baltistan. Annual trade between China and Pakistan has risen from less than $2 billion in 2002 to $6.9 billion, with a goal of $15 billion in 2014. Sost dry port is the first formal port at the border between China and Pakistan, enabling customs clearance and other formalities for goods moving from the city of Kashgar and the surrounding Xinjiang Autonomous Zone in China to the commercial centres of Pakistan. The town is linked by the Karakoram Highway to Gulmit, Aliabad, Gilgit and Chilas in the south and the Chinese cities of Tashkurgan, Upal and Kashgar in the north.

Wakhi and Brushki are the main languages spoken here.