Pasto, officially San Juan de Pasto, is the capital of the department of Nariño, in southern Colombia. Pasto was founded in 1537 and name…Pasto, officially San Juan de Pasto, is the capital of the department of Nariño, in southern Colombia. Pasto was founded in 1537 and named after indigenous people of the area. In the 2018 census, the municipality had a population of 392,930. Pasto is located in the Atriz Valley on the Andes cordillera, at the foot of the Galeras volcano.