the longest land border shared by mainland France is the Spanish border (623 km), just before the border with Belgium (620 km).
The oversea department of French Guiana has a land border of 763 km with Brazil.
France is said to share 4,139 km of borders with 11 neighbouring countries, from shortest to longest border:
Monaco 4
Netherlands 10 (in the isle of St Martin, Carribean)
Andorre 57
Luxembourg 73
Germany 451 km
Italy 488
Suriname 510 (with the département of French Guiana)
Switzerland 573
Belgium 620
Spain 623
Brazil 730 (with the département of French Guiana)
Another "neighbor" is Australia, on both sides of "la Terre Adélie". However, as "la Terre Adélie", a strip of land located in Antartica, does not enjoy the territorial and international rights and procedures, this is not listed as a frontier.
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Afghanistan shares the longest border with Pakistan at 2,600 Kms.
Sweden shares its longest border with Norway, which is located to the West of the country. This border is 2542 miles long. Its Eastern border is shared with Finland and is much shorter, about 1/3 that length.
India shares the longest border with Bangladesh with 4096 Kilometers
Afghanistan.
Bangladesh shares the largest border with India; their shared border is 4,053 kilometers long. At 1,463 kilometers long, Burma has the second-longest shared border with India.
France
Afghanistan shares the longest border with Pakistan at 2,600 Kms.
Brazil shares its longest border with Bolivia.
The country that shares the longest border with Pakistan is Afghanistan, spanning approximately 2,430 kilometers (1,510 miles).
Pakistan shares the longest border with Afghanistan. It stretches on for over 1500km.
Bangladesh
CanadaCanada shares the longest border with the US.
France and Poland have both a border with Germany.
Alaska
Sweden shares its longest border with Norway, which is located to the West of the country. This border is 2542 miles long. Its Eastern border is shared with Finland and is much shorter, about 1/3 that length.
There is no one country which shares a border with France, Switzerland and Yugoslavia. And, Yugoslavia has not existed since 1992.
India shares the longest border with Bangladesh with 4096 Kilometers