El Polen from Barranco, Lima, Peru, can be considered the first andean psychedelic group ever.
Their first album, "Cholo", released in 1972, was the soundtrack of a movie based on the life of Peruvian soccer player Hugo Sotil. Their music was a mixture of traditional andean folk with native instruments (quenas, antaras) and rock instrumentation, creating a unique style where violins sounded like fuzz guitars. El Polen released another album, "Fuera De La Ciudad" in 1973, continuing with their pioneering style.

Read more about El Polen on Last.fm.