List of countries that border only one other country

This is the list of countries that border only one other country, with only land borders being counted. Some of these countries have several neighbours "across the sea". As an example Denmark "borders" Sweden and Norway by sea, and Canada has sea boundaries with Denmark (between Baffin Island and Greenland) and France (between the island of Newfoundland and the territory of St. Pierre and Miquelon). Other countries, such as Sri Lanka, border only one other country by sea.

Territory leased or ceded by one country to another for perpetual use, but not in sovereignty, such as Guantanamo Bay Naval Base in Cuba, or memorials, such as the American Cemetery in France, do not constitute true territorial borders, because the land occupied remains a formal part of the host country.

Borders relevant to this list may include short borders in the middle of man-made constructions. Artificial islands and causeways are permanent geographic features.

In some cases, a dependent territory of one nation borders another nation.

There were many countries that historically had only one neighbour. Some no longer exist while others now have either no land borders or borders with more than one nation due to border changes.

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