The highest peak in the Sierras chicas, near Capilla del Monte; the Cerro de Uriturco.

From Wiki:

Since 1986 the Uritorco has been mentioned in media reports of UFO sightings, extraterrestrial visits, and visions of “parallel dimensions”. The nearby Capilla del Monte and the base of the Uritorco attract many New Age supporters and tourists interested in the alleged mystical/energetic qualities of the mountain and other paranormal phenomena, and a local artisan industry has developed around this topic.