The Fort of Tolpán was built in 1657, by the order of the governor of Pedro Porter Casanate to the captain Alonso de Córdova and Figueroa in the Tolpán or Trolpán River, then mapuche territory during the War of Arauco in Chile.

The Tolpán River was the name at that time so it is now the lower part of the river Renaico and the river Vergara at the confluence with the river Renaico which empties into the Bio Bio River. Tolpán or Trolpán is a contraction of the words of the mapudungun Thol that means "in front", and of pangui, that is to say "lion" or puma, which would mean "in front of the lion". Located at the confluence of the rivers Renaico and Vergara, the captain of Cordova and Figueroa used the fort to act against the Mapuche in the surrounding lands during the Mapuche insurrection of 1655, but was abandoned a few years later. After Chile's independence, when the Chilean army entered the area during the 1860s, Colonel Cornelio Saavedra began the studies to install a fort on the banks of the river Renaico at the same site of this fort that did not becomes concrete. Source

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