China has the longest land border in the world.
At approximately 13,500 miles, China has the longest land border which it shares with 13 of its neighbors. The thirteen neighbors are Mongolia to its north with whom it shares its longest border of 2,906 miles. Russia lies to its northeast, North Korea to its east, Vietnam, Laos, Myanmar, Bhutan, and Nepal to its south, India to its southwest, Afghanistan and Tajikistan to its west, Kyrgyzstan and Kazakhstan to its northwest. China also shares borders with its two special territories – Hong Kong and Macau to its southeast.
At 12,577 miles, Russia has the second longest land border which it shares with 14 of its neighbors. The fourteen neighbors are North Korea and China to its southeast, Mongolia and Kazakhstan in the south, Azerbaijan and Georgia to its southwest, Ukraine, Belarus, Latvia, Lithuania, Estonia and Poland to its west, Norway and Finland to its northwest. Its longest border is with China at 2,615.5 miles.
At 10,492 miles, Brazil has the third longest land border which it shares with 10 neighbors. The ten neighbors are Uruguay and Argentina to its south, Paraguay and Bolivia to its southwest, Peru to its west, Colombia and Venezuela to its northwest, Guyana, Suriname and French Guyana to its north. Brazil shares its longest border with Bolivia at 2,113 miles.
Country sharing the longest single border
At 5,525 miles, USA and Canada share the longest international border in the world. The border is complex as the line is not straight for the entire stretch due to its unique geography.
Countries with the longest single segment land border
Russia and Kazakhstan share a 4,254 miles single segment border that makes it the longest in the world.
USA and Canada share a 3,985 miles single segment border that makes it the 2nd longest in the world.
Argentina and Chile share a 3,200 miles single segment border that makes it the 3rd longest in the world.