Pakistan and Afghanistan share a long, mountainous border, known as the Durand Line, which successive Afghan governments have not formally accepted. Cross-border militancy, refugee movements and trade through crossings such as Torkham have long defined relations between the two countries, and counterterrorism cooperation in the region has been a recurring theme of US–Pakistan relations.
View from Michni Post towards the Torkham border, Khyber Pakhtunkhwa