Aconquija National Park

Aconquija National Park, long known as Campo de los Alisos, protects an extraordinary altitudinal sweep on the eastern flank of the Sierra del Aconquija in southern Tucumán, running from around 800 metres of humid yungas forest to the glaciated summit of the Cerro del Bolsón above 5,500 metres. Walking up through it means passing in a day or two from tree ferns and howler-monkey forest to alder woods, then to open high grassland and finally to rock and ice. High on those grasslands stand the ruins of La Ciudacita, an Inca site of stone enclosures and platforms near 4,400 metres, one of the southernmost Inca installations known, reached only by a demanding multi-day trek. Lower down, day walks follow the Los Alisos river through the forest.

What you actually see

• The forest trails - yungas jungle along the Los Alisos river near the entrance.
• The altitude sweep - forest giving way to grassland and then to peaks and ice.
• La Ciudacita - remote Inca ruins high on the grasslands, days away on foot.
• The wildlife - taruca deer, condors and hundreds of bird species.

When to go

April to November, the dry season, for river crossings and trekking; the summer rains swell the rivers and make the access road difficult. High-altitude routes are only sensible in the stable months and need experience. Weather changes fast on the ridges.

Honest expectations

This is a walker's park with no roads into the high country, minimal facilities and no shops; everything must be carried. The trek to La Ciudacita is serious multi-day mountain travel at altitude, not a day hike. Even the lower trails involve fords that rise quickly after rain.

Nearby

Concepción is the gateway town; Tafí del Valle lies north over the range.