Aconquija National Park, National park in Tucumán Province, Argentina.

Aconquija National Park is a protected area in Tucumán Province, created by national law no. 27451 of 17 April 2018 and covering about 70,000 ha in two core sectors. It includes Portal Campo de los Alisos, the former Campo de los Alisos National Park of 1995, with 16,067 ha, and a national reserve sector of 52,000 ha. The park protects Yungas rainforest, mountain forest and high-Andean puna, from around 1,000 m up to snow-covered peaks near 5,000 m.

The protected area was originally founded in 1995 as Campo de los Alisos National Park and received its current name through legislation in 2018. The name change accompanied an expansion of the park to better align its boundaries with the natural mountain ranges.

At Ciudacita, about 4,400 m up, stand ceremonial enclosures and other Inca buildings counted among the empire's southernmost. Reaching them takes a four-day guided walk and climb, through high-Andean country where snow can fall at any time of year.

The park entrance is at Portal Campo de los Alisos, in the Chicligasta department, reached from Concepción, where the park administration has its seat. The site of Ciudacita lies at 4,400 m and can only be reached on a four-day walk with an authorised guide; snow is possible there at any time of year.

At 4,400 m in the park stand the ruins of Ciudacita or Pueblo Viejo, ceremonial enclosures and buildings counted among the southernmost of the Inca empire. Reaching them takes a four-day walk and climb with an authorised guide, in a high-Andean climate where snow can fall at any time of year.