Pampa Alta Pass also known as Puesto Viejo (Old Post), is a boundary pass between Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 and Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

, joining Aisén Region and Chubut Province

Chubut Province

Chubut a province in the southern part of Argentina situated between the 42nd parallel south and the 46th parallel south , the Andes range separating Argentina from Chile, and the Atlantic ocean...

. The elevation of the pass is 865 metres (2,838 feet) above sea level. The pathway in this locality is a gravel road

Gravel road

A gravel road is a type of unpaved road surfaced with gravel that has been brought to the site from a quarry or stream bed. They are common in less-developed nations, and also in the rural areas of developed nations such as Canada and the United States. In New Zealand, they are known as 'metal roads'...

 and the traffic is permanent between 8 am and 8 pm in winter and between 8 am and 10 pm in summer. To leave Chile, it is necessary to obtain a pass from the international police in Coihaique. The nearest police assistance is situated 4 km (2.5 mi) away from the pass and the closest inhabited places are Balmaceda

Balmaceda, Chile

Balmaceda is a Chilean village located south east of Coyhaique in Aisén Region. Balmaceda has around 500 inhabitants, and has Aysen Regions largest airport and meteorological station; Balmaceda Airport. The first settlers arrived into the zone in early-20th century after being expelled from...

 and Coihaique, in Chile.

Pampa Alta has the coldest unofficial recorded temperature in South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

, of -40 °C (-40 °F), on June 21, 2002.