Day 41 - Up into the Andes

Our tour today followed the Mendoza River up to the border with Chile - an impressive trip.

The Andes climb up from Mendoza (at 2,500 feet) in three separate ranges: the foothills (topping out around 11,000 feet), the frontal (peaking around 21,000 feet) and the principal (with the highest peak in the southern hemisphere, Aconcagua, at 23,000 feet). We didn't climb the peaks but did get pretty high.

After picking up other tourists, we caught the Mendoza River outside Lujan de Cuyo and climbed past a tall hydroelectric dam through a series of steep switchbacks and along the reservoir. The we followed the deep valley up the foothill range. The Mendoza (and the glaciers before it) cuts a channel through a variety of rock with the valley walls jumping up well over a thousand feet. Throughout the climb, we marveled at the colors of the rocks, red, yellows, whites, greens, olives, browns, and blacks mixed and swirled in layers and curves. The erosion of these rocks leaves multi-colored fans of gravel falling down the precipitous slopes.

The Andes are formed by thrusting and folding were the Pacific plate collides with five continental plates along the west coast. Subduction action creates volcanoes that push magma up through the folds to create over 40 extinct, dormant, and active cones along the way.

The road, Argentina's Ruta 7, is the major route between the country and Chile. It carries 500 to 800 trucks a day and passes through 14 tunnels as it climbs. Also climbing through the valley is the abandoned tracks of the Trans-Andes railway, built in 1907 but closed in the 1970s when the constant clean up of rock slides became too much to bear. The tracks, derelict stations, and rusting bridges remain.

The Mendoza River valley is deep with the sediment and alluvial deposits washed down from the towering side hills and canyons. The river cuts through these deposits as it rushes to the plains. For miles, the river has cut a tall vertical wall through the sediment that jumps straight up hundreds of feet.

We topped the foothills and came into a lush valley and the town of Uspallata (6,500 feet). The river valley is barren with only low scrub brush and bare side hills. In contrast, the Uspallata valley is green with tall elm, poplar, and sycamore trees and fields growing vegetables. Here a large tributary feeds into the Mendoza. We stopped for a break at a kind of truck stop.

Our tour continued up the frontal range. Our guide continued her near constant stream of explanations about the few towns the railroad, the history, the formations, and the rocks and hills in Spainish and English. The tunnels kept coming, the steep side hills kept climbing, and the river churned through the valley - although the flow was noticeably less.

The road is two lanes, well paved, well-engineered, and carries moderate traffic. The colors of the rocks continued to astound us. Near the town of Polvereda, another military base with not much else, we passed the Vaca River joining the Mendoza. This marks the start of the start of the last range. The river, of course, cuts through the ranges so the road keeps a steady climb even though the mountains climb and descend. We passed a small ski resort, now closed for the summer.

We soon entered the Provincial Park Aconcagua. This is the jumping off point for hikers wanting to climb the trails around and up the highest mountain in South America. Our tour stopped at the tiny visitor's center and took the short walk to a viewpoint to gaze at the peak, some 15 miles away.

A bit further on, we started into the third range and turned from the Mendoza to follow one of its three tributaries, the Cueva River. There are customs posts along the way where trucks entering the country are inspected. We passed the tiny hamlet of La Cueva (8,500 feet). The hamlet has only 10 year-round residents but swells to about 100 when the snows cease and the summer tourists start coming. Here we left Ruta 7 for a gravel road to climb into the third range.

This narrow road climbs a series of switchbacks up the steep side hill with more than a half-mile elevation change in perhaps two miles horizontal distance, although the road snakes maybe ten miles as it climbs. The views over the Cueva valley below and the tall peaks all around are breathtaking. At the top of this climb, at just under 13,200 feet, is the Christ the Redeemer monument. The monument honors the 1904 peace pact between Argentina and Chile and sits exactly on the borderline. You can walk ten steps from one side of it to the other and cross into the other country. The bronze sculpture was made of melted down cannons used in the war. It is a 20-foot statue of Christ holding a cross. The wind at the top was strong and constant and we bundled up to walk around the area. The driver played the San Martin march on the way up the switchbacks (this was one of the passes his army used to cross the Andes into Chile) and played the Argentine national anthem on the way down. The Argentine passengers sang along.

In La Cueva, we ate a good buffet lunch before starting the return to Mendoza city. We made one more stop on the way at the Inca Bridge. This is a natural formation over the Cueva River formed hundreds of years ago. It sits where a series of thermal springs spout from the mountain base. In the early 1900s, a hotel sprang up to cater to the people coming for chores. The mineral-laden waters deposit a multi-colored sheen of Crystal's over the bridge and sides of the river channel. Thus deposit has protected the bridge from erosion. Our tour wound back down the river canyons to Mendoza, arriving about 19:30, twelve hours since our start. It was a great trip with marvelous scenery and vistas.Read more