Kazakhstan–Russia border

The Kazakhstan–Russia border (Russian: Казахстанско-российская граница) is the 6,846 kilometres (4,254 mi) international border between the Republic of Kazakhstan and the Russian Federation, the second longest in the world between two countries, after the Canada–United States border. It is in the same location as formerly the administrative-territorial border between the Kazakh SSR and RSFSR.

The border assumed its modern shape in 1930, and became an international border upon the dissolution of the USSR in 1991.

The border between Kazakhstan and Russia does not form a border between the territories populated by Kazakhs and Russians. Kazakhs, Russians and other ethnic groups (Germans, Tatars, and Ukrainians) live on both sides of the border.

Roads and railways were not built with this border in mind, so when the border became international, for example one branch of the Trans-Siberian Railway was interrupted by two border crossings at Petropavl.