Qal'ai Khumb (,, Qal‘a‘i Xumb/Qal'haji Xumв — meaning fortress on the banks of the river of Khumb) or Qal'a-i-Khum, also Kalai-Khumb (transliterated from ), is a border town located in the Gorno-Badakhshan Autonomous Region of Tajikistan, next to the border with Afghanistan. In the past it was the center of the independent Principality of Darvaz. It is now the capital of the Darvoz District of Tajikistan. The Pamir Highway meets here the Panj River. The town is an important overnight rest stop between Kulob and Khorugh, located at a distance of 168 km from Kulob (or 368 km from Dushanbe) and 235 km from Khorugh. It has several hotels to accommodate travelers on their way between cities. The town is almost entirely surrounded by the Pamir Mountains. The town is connected by road with Afghanistan via the Tajik–Afghan Friendship Bridge. The Saturday cross-border trade market, which was closed for several years, has been reopened recently.