El Leoncito National Park is a stunning protected area in Argentina known for its clear skies, high-altitude landscapes, and rich biodiversity, offering exceptional opportunities for hiking, astronomy, and wildlife observation.
Located in the province of San Juan, Argentina, El Leoncito National Park encompasses a vast area of high Andean foothills and plateaus at altitudes ranging from approximately 1,600 to 2,600 meters above sea level. The park is situated within the Sierras del Tontal mountain range and is renowned for having some of the clearest skies in South America, making it a premier destination for astronomers and stargazers. Established in 2002 to protect its unique environmental assets, the park preserves important ecosystems characterized by arid scrublands, dry montane forests, and diverse wildlife including guanacos, foxes, Armadillos, and many bird species such as the Andean condor.
Geographically, the park features rugged terrain with deep valleys, rocky cliffs, and small rivers that sustain the local flora and fauna. Historically, the region bears traces of indigenous Cacán and Diaguita cultures, with archaeological sites nearby showcasing their early settlements. Recreationally, El Leoncito National Park offers hiking trails that navigate through scenic vistas and natural landmarks, opportunities for wildlife viewing, and especially nighttime astronomy tours supported by the nearby Leoncito Astronomical Complex (CASLEO), one of Argentina’s main observatories.
Visitors are drawn by the park's tranquility, dramatic desert landscapes, and the chance to experience some of the clearest and darkest skies in the Southern Hemisphere. The remoteness and pristine condition of El Leoncito make it a captivating destination for adventurers and nature enthusiasts seeking solitude and natural beauty away from urban centers.
Leoncito Astronomical Complex (CASLEO) – premier astronomical observatory
High-altitude viewpoints with panoramic vistas of the Andes foothills
Rare sightings of Andean wildlife such as guanacos and condors
Clear, dark skies ideal for stargazing and astrophotography
A world-class astronomical observatory located within the park, offering research facilities and guided night sky tours.
The rugged mountain range providing dramatic landscapes and diverse ecosystems within the park boundary.
One of the clearest and darkest night skies globally, ideal for observing the Milky Way, planets, and deep-sky objects.