Penco (Mapudungun: "Peumo water") is a Chilean city and commune in Concepción Province, Bío Bío Region on the Bay of Concepción. Founded as the city of Concepción del Nuevo Extremo on February 12, 1550 by Pedro de Valdivia, it is the third oldest city in the country after Santiago founded first in 1541 and La Serena second in 1544.