Junín is a department and region in the central highlands and westernmost Peruvian Amazon. Its capital is Huancayo.

Huancayo is the capital of the Junín Region and Huancayo Province, in the central highlands of Peru, in the Mantaro Valley and is crossed by the Shullcas, Chilca and Mantaro rivers. It was founded as a reduction by the name Santísima Trinidad de Huancayo on 1 June 1572, by Don Jerónimo de Silva, a Spanish conquistador. It is the fifth largest city in Peru, with a population of 500,000 and is among the highest cities in Peru, with an altitude of 3,256 meters above sea level. It is considered the economic and social center of central Peru