The M41, known informally and more commonly as the Pamir Highway is a road traversing the Pamir Mountains through Afghanistan, Uzbekistan, Tajikistan, and Kyrgyzstan in Central Asia. It is the only continuous route through the difficult terrain of the mountains and serves as the main supply route to Tajikistan's Gorno-Badakhshan Autonomous Region. The route has been in use for millennia, as there are a limited number of viable routes through the high Pamir Mountains. The road formed one link of the ancient Silk Road trade route.
Sources disagree on the termini of the highway, with Mazari Sharif, Afghanistan; Termiz, Uzbekistan; Dushanbe, Tajikistan; and Khorog, Tajikistan all being offered as the beginning of the highway. All sources, however, agree that the highway ends in Osh, Kyrgyzstan. Today, the route is part of the M41 highway, which starts at Termiz and ends at Kara-Balta to the west of Bishkek, Kyrgyzstan.
The route passes northward through Termiz before turning east and crossing into Tajikistan. It then follows a general eastward route through Dushanbe, the capital of Tajikistan, to Khorog, crossing the Kafirnigan, Vakhsh, and Bartang Rivers. From there, it continues east for about 310 kilometers to Murghab, where it crosses the Murghab River. The highway then passes through the 4,655-meter (15,270 ft) high Ak-Baital pass and past Lake Karakul before crossing into Kyrgyzstan to its terminus in Osh. The stretch of road between Khorog and Osh attracts a small amount of tourism due to its rugged natural beauty.
The Pamir Highway is designated as route M-41 over much of its length in Tajikistan and Kyrgyzstan, and is known as the second-highest altitude international highway in the world (4,655 m). The section between Dushanbe and Murghab has the European route number E 008. Construction and maintenance levels vary substantially along the highway. The roadway is paved is some areas, but is mostly unpaved. The road is heavily damaged in places by erosion, earthquakes, landslides, and avalanches.