Aconcagua expedition in Argentina

Cerro Plomo is a "big one". The Incas chose it as an "Apu" (guardian in the quechua language), because it completely dominates the central valley of the Maipo river, generously providing it with water from its many glaciers. The glaciers of its south face give birth to the Molina river, which after joining the Yerba Loca stream forms Santiago’s main river, the Mapocho. Glaciers of the north and west faces feed the Maipo river, first forming the Olivares river, main afluent of the Colorado river, which before leaving the internal valleys of the Cordillera, flows into the copious Maipo.
Cerro Plomo is visible from almost every point of the central valley of the Maipo, from Graneros to Lampa. Naturally, it is also visible from every highpoint of the central Cordillera, including from those of the Cordillera de la Costa (coastal mountain range). For this reason, and because of its tremendous mass, the Plomo was chosen as a sanctuary by the Incas. On its slopes, and on top of its summit, many rituals were celebrated, especially those directed towards the sun, their principal god, "Inti"; also when strange phenomena such as sickness, wars, and disease ocurred. The most known ceremony, the "Capac Cocha", consisted in the sacrifice of young men and maidens. There is plenty of evidence of these ceremonies all around Plomo’s slopes : at Plomo’s summit, for instance, there are some simple but not rough constructions of stones, and nearby its highest point a buried Inca boy was discovered, interrupting his peaceful sleep on Plomo, which lasted more than five hundred years. The discovery took place on February 1^st 1954, around three o’clock, when the "arrieros" (cowboys of the Andes) Luis Ríos Barrueto, Guillermo Chacón Carrasco and Jaime Ríos Abarca reached the summit. They were probably seeking Inca treasures; it is common knowledge among "arrieros", or it was some time ago, that next to the young victims the Incas also buried valuable gold pieces (the members of this kind of expeditions are known as "huaqueros", since these burials are known as "huacas"). Today, the mummy is in the Museo de Historia Natural de Santiago, though not on view to the public. The museum has not been able, until now, to collect the needed resources to show and maintain the mummy in a place which permits doing so without disintegrating it; the mummy is very sensible to the rays of light.

Access
Via La Parva
From Santiago (Avenida Las Condes), take the road to Farellones, continue past Farellones (do not turn right at the turn to Valle Nevado) to the La Parva Ski Center. Continue, if possible, to the ski center’s highest point, depending on whether the road up the ski runs is open and clear of snow (ask local workers to show the way). Via this road you will reach the end of the last lift, called Piuquenes, right next to the pass between Cerros Franciscano and Falsa Parva. From the beginning of the road to Farellones up to Piuquenes, it takes between one hour and one hour and a half by car. From Piuquenes to Piedra Numerada, it takes between two and two and a half hours walking. If the road up the ski runs isn’t open, consider 2 or 3 hours of heavy hiking from the ski center to the pass (if there is no snow), which is at 3,470 meters above sea level.

Approach
Piedra Numerada (3,370 m) is the natural place for sleeping the first night. In the middle of a great vega (plain covered with high altitude vegetation and with abundant water), right next to the Cepo River, Piedra Numerada was used for many years by the arrieros to count the animals before taking them down to the valley just before winter arrived. It is a spacious place, with plenty of water and lots of room for setting up camp. Some boulders and stone parapets are a reference point. Beware of mice : do not leave food or garbage at their reach.

The Climb
Piedra Numerada — La Hoya
The trail from Piedra Numerada to La Hoya follows the stream most of the time and it climbs above and to the right of the waterfall visible from Piedra Numerada. In more or less 4 hours, one should reach La Hoya, though this will depend greatly on the physical condition and acclimatization of each climber.
La Hoya (4,200 m)
La Hoya is reached just after going up a grey mound that is visible from an orange shelter (Refugio Federación, houses 4 people comfortably) located at a side of the trail which heads in Plomo’s direction. The site of the orange shelter is an alternative campsite. A better rest (with less "puna", or altitude sickness) can be obtained here, which may compensate the extra effort during the summit day. This place is at approximately 4,100 meters.
La Hoya is a sandy place very near the Iver Glacier’s moraine. It is a place somewhat protected from the wind, but is is also very common to get "puna" or high altitude sickness here, more than in other places as high. Other possible campsites are "Los Espejos" and the "Refugio de Agostini". The first is at aproximately 15-20 minutes from La Hoya following the trail that leads to the summit. Just in the middle of a section covered with stones and boulders, there are two little ponds of pristine waters. The place is fine for setting up camp, since it is protected from the wind, it is less crowded than La Hoya and, according to some isolated studies, it is somewhat less "puna" prone. The "Refugio de Agostini" is a modest but efficient wooden shelter at the foot of the Plomo’s main scree slope. It was built by the Federación de Andinismo in the sixties and today isn’t in a very good state. Built at 4,600 meters, the Refugio de Agostini is very exposed to the wind, and has no water near it, though there is snow for melting. The shack allows for a low three person tent to be set up inside. The choice of which of these places to choose for resting before the summit bid is crucial. The extra work that carrying all the gear and food up to the Refugio de Agostini isn’t always compensated with an equivalent saving during the final ascent; this will depend largely on each climber’s capacity. With heavy loads, from La Hoya to the Refugio might take more than and hour and a half. The same distance is covered in half the time during a normal summit bid. For those who enjoy socializing, we recommend La Hoya. For those who would rather be alone, Los Espejos will suit them better. Climbers on a training program should go up to the Refugio. For those very "puna" prone, I recommend staying below La Hoya, at the Refugio Federación.
La Hoya — Summit
From La Hoya turn back towards the valley and then follow the trail that overcomes the promontory that guards La Hoya from the South, turning again towards Plomo. The trail goes East up to Los Espejos, where it turns North, towards the Iver Glacier, thus circling La Hoya, which is always visible from up high. Later, the plateau where the Refugio de Agostini lies is reached. At this point (good place for resting and hydrating) a very long scree slope starts.
Several winding trails reach some rock turrets by different paths, visible from everywhere; these mark the end of the scree. The most common way up from here (less steep and on firmer ground) is to circle these rocks from the East (going opposite to Cerro Plomo and to the right). Then comes a traverse just above the Iver Glacier, along a trail over big rocks. This traverse ends at Plomo’s summit ridge. A few more minutes and the upper crossing of the glacier is reached. Just above a stone dome there is a stone parapet which protects from the wind and serves as a resting place before crossing the glacier ("Pirca del Inca", 5,050 m where the Plomo’s Mummy was found); from here the mountain’s northern glaciers become visible and for the first time is one convinced that the Leonera summit was left below.
The glacier’s crossing has a gentle incline and is free of crevices (the crossing takes between 15 to 30 minutes on a normal year at its narrowest part). However, the ice may be hard, making the use of crampons and extreme care necessary : it takes but a few meters sliding to reach the point where the gradient changes violently, exposing one to a 600-meter fall.
Once the glacier crossed, it takes less than an hour to reach the summit.
The summit
From La Hoya it takes between 4 and 8 hours to reach the summit, varying widely with the weather conditions and the climber’s fitness. A good reference is six hours from La Hoya. The way down takes approximately half the time of the ascent.
This classical central zone mountain’s summit is a fine spectacle : from it, all the high summits of the central zone are visible, from Mercedario in the North, to Volcán Maipo in the South; the view thus covers nearly 300 kilometers. The summit is broad, and it takes a few minutes to cross up to its highest point, marked by a cross and memorial to the fallen climber of the first Chilean expedition to Mount Everest, Víctor Trujillo. The summit is normally whipped by the Boreas (north wind), and the wind chill makes one feel very cold, unless adecuate protecion against the wind is used.