 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.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.