Chile and Argentina share more than 5,000 miles of border, most of them drawn on the imposing peaks of the Andes. With over 40 border crossings between the two countries spread over the mountains, the most spectacular and important one is Paso de los Libertadores, also known as the Paso del Cristo Redentor, in particular, the stretch that locals call it, rightly, Los Caracoles (Snails Pass).
Due to the unique location and the climb in elevation over thousands of feet (the pass reaches an elevation of 3,200 m (10,499 ft) above the sea level, and passing through remote areas, it is important when driving in these conditions to be prepared. It is the most important step between the capital of Chile, Santiago, and the Mendoza region of Argentina. The Argentina side turns out to be a gentle ascent, up relaxed through rugged mountain scenery of the area until the hole in the tunnel entrance.
The crossing, in the summit, is actually a tunnel: the Cristo Redentor tunnel, located at 3,209 m altitude and with 3,080 meters long, of which 1,564 are in Chilean territory and 1,516 in the Argentine side. Opened in 1980, the tunnel is at an elevation of 3,175 m (10,417 ft), and the path can be closed during winter because of heavy snows blocking both ends and the threat of rockfall.
Its name comes from the 4 ton Christ the Redeemer of the Andes (Cristo Redentor de los Andes) statue placed in 1904 near the entrance of the Argentine side at an elevation of 4,000 m (13,123 ft). However, access by the Chilean side is another story. The landscape remains the same, but the road gets higher with much more quickly, forcing a winding route so perfectly delineated that, seen from the air, looks like the coil of a refrigerator. The traffic is intense, especially for heavy vehicles facing this part with calmness and resignation, forming long convoys that slow pace, amounting port. Viewed from a distance the trucks seem snails.
The road is covered with snow for the most part of the year. Los Caracoles is a series of hard switchbacks on an extremely steep incline. The snow together with nature of the road requires extreme patience and skill to negotiate. The surface of the road is asphalted, and chains or snow tyres can be required troughout the year. However, this road is maintained pretty regularly and does not have a morbid accident record. Cargo trucks and even double-Decker tourist buses travel through the road on a daily basis, and it's quite an experience.
The pass is also known as Uspallata Pass, Bermejo Pass or Cumbre Pass