Tralcán ( mapudungun for '' thunder '' ) is a triangular-shaped mountain , which is located near Riñihue Lake , Chile . It is located south of the outflow dividing western Riñihue in two arms . Despite having been sacred to the huilliches for centuries , the mount became famous when several landslides near Tralcan dammed the Riñihue Lake after the 1960 Valdivia earthquake . The water levels in the lake rose more than 20 m and became a threat to the existence of Valdivia city . These events came to be known as The Riñihuazo ( " El Riñihuazo " in Spanish ) . There is evidence that a similar landslide occurred after the 1575 Valdivia earthquake
1960 Valdivia earthquake
1960 Valdivia earthquake
Tralcán