Paso Internacional Los Libertadores

The Paso Internacional Los Libertadores, also called "Cristo Redentor", is a mountain pass in the Andes between Argentina and Chile. It is the main transport route out of the Chilean capital city Santiago into Mendoza city in Argentina and so carries quite heavy traffic.
Overview.
From the Argentine side the route to the pass is a slow, gentle incline until entering a tunnel at approximately elevation. On the Chilean side the slope has a far higher grade, and the road descends down a long series of switchbacks to make the descent.
Opened in 1980, the Tunnel of Christ the Redeemer (Spanish: Túnel Cristo Redentor) is long, and serves as an important land crossing between Chile and Argentina. At the middle of the tunnel is the national border, which is the termini of Chile Route 60 and Argentina Route 7. The path can be closed during winter because of heavy snows blocking both ends and the threat of rockfall.
Its name comes from the four-ton "Christ the Redeemer of the Andes" ("Cristo Redentor de los Andes") statue placed in 1904 near the Uspallata Pass at an elevation of . The pass was the highest point of the road before the opening of the tunnel lowered the maximum elevation by , eliminated 65 switchbacks and shortened the route by .
On 19 September 2013, nearly 15,000 Chileans got stranded on the Argentine side, when the pass had to be closed for 10 hours because of freezing temperatures and between 40 and 50 centimeters of snow.
Alternative proposed tunnels.
In order to ease the dependence on the only tunnel in the area and to permit year-round crossing, two lower tunnels have been proposed. One of them is the "Túnel Juan Pablo II" ("John Paul II Tunnel"), which would be constructed at an altitude of between , long, to join the towns of Horcones, Argentina and Juncal, Chile.
Another proposed tunnel, named "Paso Las Leñas" ("Las Leñas Pass"), at an elevation of and of length, would connect El Sosneado in Argentina (near San Rafael) and Machalí, Chile.
The Aconagua Bi-Oceanic railway is a proposal for a base tunnel under this pass.