It may come as a surprise that the country France shares its longest border with is nowhere near Europe. The border is actually with a country 5,000 miles away in South America.

It stretches 450 miles, which is longer than France's 387-mile border with Spain. It is also longer than France's border with Belgium, Germany, Switzerland, Italy or any other European country.

France's longest border is actually with Brazil, despite the two nations being on entirely different continents.

It lies between the Brazilian state of Amapa and French Guiana, at the northernmost edge of Brazil. Part of the border is formed by the Oyapock River, which is crossed by the Oyapock River Bridge, in the Amazon Rainforest.

This connects the towns of Saint-Georges in French Guiana and Oiapoque in Brazil. The basis of the border dates back to the Peace Treaty of Utrecht signed between France and Portugal in 1713. This set the boundaries between the colonial holdings of both kingdoms in South America.

Brazil was the successor of the Portuguese Empire in 1822 and has since disagreed with France about the location of the Japoc River. The disagreement, known as the Amapa Question, saw France believe the river mentioned in the treaty was the Araguari River, while Brazil considered it to be the Oyapock River.

Military posts were established by France and Brazil along the border. They saw Franch troops invade Brazilian territory up to the Araguari river in 1895.

After years of disagreement, the dispute was eventually settled in favour of Brazil. An international arbitration in Switzerland examined documents to conclude that the border should be set at the Oyapock River in 1900. This is where it has remained every since.