Nacimiento is a Chilean city situated in the Bío Bío Province, Bío Bío Region, 550 km (342 mi) south of Santiago, and 104 km (65 mi) from the closest major city in the region, Concepción.

The Biobío River is the second largest river in Chile. It originates from Icalma and Galletué lakes in the Andes and flows 380 km to the Gulf of Arauco on the Pacific Ocean.