Avianca S.A. (Spanish acronym: Aerovías el Continente Americano, formerly Aerovías Nacionales de Colombia) has been the national flag air carrier of Colombia since 1919, making it the second-oldest continuously running airline in the world behind Netherlands-based KLM. Likewise it is the largest airline in the country. Avianca was founded in Barranquilla, but its main operation base and headquarters are in Bogotá adjacent to El Dorado International Airport. Avianca belongs to South American conglomerate Synergy Group.