Lava lake in Villarrica Volcano

Snow-covered Villarrica, one of Chile's most active volcanoes, rises above the lake and town of the same name. The volcano is also known as Rucapillán, a Mapuche word meaning "House of the Pillán". It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andean chain along the Gastre Fault. This alignment crosses the N-S running Liquiñe-Ofqui Fault. Villarrica is one of only four volcanoes worldwide known to have an active lava lake within its crater. Villarricas lava is basaltic-andesitic but is quite explosive despite this. Two large ignimbrite layers are visible at its surroundings; the Licán Ignimbrite and later the Pucón Ignimbrite. About 25 scoria cones dot Villarica's flanks. It also has volcanic caves. The volcano, along with Quetrupillán and the Chilean portion of Lanín, are protected within Villarrica National Park.

In 1964 Villarrica had a strombolian eruption that caused lahar flows. The lahar destroyed a settlement on the shores of Calafquén Lake, Coñaripe, which was later reconstructed further east.