Countries With the Longest Land Borders

The border between the United States and Canada is the world's longest continuous border.  Editorial credit: Brian Kenney /
The border between the United States and Canada is the world's longest continuous border. Editorial credit: Brian Kenney /

Borders are the geographic boundaries between countries. They are established through treaties and other such agreements that delineate boundary lines. These borders are often controlled by the two countries that share it, with border crossings at certain points. Some border remain points of contention between states who are unable to agree on where the border lies. The following are the 30 longest borders of the world.

10. Mexico–United States- 3,155 km

The border between the United States and Mexico is the world's tenth longest, covering 3,155 km. The San Ysidro border crossing between the US and Mexico is the world's busiest land border in terms of traffic.

9. Pakistan–India - 3,190 km

The border between Pakistan and India is the world's ninth longest, stretching for 3,190. The border is tied to the Line of Control, which separates the highly-contested territory of Kashmir. This border is considered to be among the world's most dangerous.

8. Brazil–Bolivia - 3,403 km

Brazil is the fifth largest country in the world by land area, and has some long borders to prove it. The country's longest border is the one that it shares with Bolivia, which stretches for 3,403 km.

7. Mongolia–Russia - 3,452 km

The eighth longest land border in the world is shared by Russia and Mongolia. It is 3,485 km long. Mongolia has only two land borders, one with China and one with Russia.

6. China–Russia - 4,133 km

The China-Russia land border is 4,133 km long. These countries, which are among the largest states in the world, share the fifth longest land border in the world.

5. Bangladesh-India – 4,142 km

The border between the South Asian countries of Bangladesh and India stretches for just over 4,000 km. The border is mostly unfenced. There are some enclaves near the border that are a point of dispute between the countries.

4. China–Mongolia - 4,630 km

The China-Mongolia land border is 4,630 km long. China, the 3rd largest country in the world, shares its 22,147 km long borders with 14 nations. However, the country to its north, Mongolia, shares the longest border with China.

3. Argentina–Chile - 6,691 km

Chile is approximately a quarter of Argentina’s size. However, due to Chile's length along the southwestern portion of South America, the two countries share the third longest border in the world that is 6,691 km long.

2. Kazakhstan–Russia - 7,644 km

The second longest land border in the world is the Kazakhstan-Russia border that is 7,644 km in length. Russia, the world’s largest nation, shares its land borders with 16 countries. The Kazakhstan border is to the south of Russia.

1. Canada–United States - 8,893 km

Canada, the world’s second largest country, shares the longest international land border with the United States. The border is divided into two: the border shared with Canada by the continental United States and the border that the state of Alaska shares with northern Canada. Eight Canadian provinces and thirteen American states run along the shared boundary. The Canada-US land border is 8,893 km long. The St. Lawrence River and Great Lakes form part of the border between the two countries.

21 Longest Land Borders

RankCountry ACountry BBorder Length (km)
1CanadaUnited States8,893
10MexicoUnited States3,155
14AngolaDemocratic Republic of the Congo2,646
15GabonRepublic of the Congo2,567
20Democratic Republic of the CongoZambia2,332

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