Argentina–Chile border

The Argentina–Chile border is the longest international border of South America and the third longest in the world after the Canada–United States border and the Kazakhstan–Russia border. With a length of 5308 km, it separates Argentina from Chile along the Andes and on the islands of Tierra del Fuego. However, there are some border disputes, particularly around the Southern Patagonian Ice Field. It is the largest border of the two countries, beating the Argentina–Paraguay and Chile–Bolivia, Argentina's and Chile's second largest borders, respectively.

Description
The northern end of the border is a tripoint it forms with those at the Argentina–Bolivia border and the Bolivia-Chile border in the arid Puna de Atacama plateau. The border extends south until reaching the sea at the same place the Strait of Magellan meets the Atlantic Ocean. Further south the border on the Isla Grande de Tierra del Fuego follows a meridian separating the island into two. This boundary reaches the sea at Beagle Channel a few kilometers southwest of Ushuaia.

In November 1984 the southern border area was finally established after long negotiations and mediation of John Paul II by the Treaty of Peace and Friendship of 1984 between Chile and Argentina, a perpetual treaty, signed at the Vatican by representatives of both countries.

On 16 December 1998, an agreement between Argentina and Chile was signed to redefine the border line from Mount Fitz Roy and Mount Daudet and finish with the historical dispute. However both countries didn't agree in the section between Mount Fitz Roy and Mount Murallón, and the border is still pending to be defined.

The territorial claims of Argentina and Chile over Antarctica partially overlap with each other. Chile claims for itself the Chilean Antarctic Territory, which is included in the Region of Magallanes and Chilean Antarctica, while Argentina claims Argentine Antarctica, whose territory is part of the Province of Tierra del Fuego, Antarctica and South Atlantic Islands.

Both countries recognize each other's territories that do not overlap with their own as stipulated in the protocols of 1947, 1948, 1964, 1971 and 1978.