Arenal Volcano, in Spanish Volcán Arenal, is an active andesitic stratovolcano in north-western Costa Rica around 90 km northwest of San José, in the province of Alajuela, canton of San Carlos, and district of La Fortuna. The Arenal volcano measures at least 1,633 metres (5,358 ft). It is conically shaped with a crater spanning 140 metres (460 ft). Arenal is geologically considered a young volcano and the age is estimated to be less than 7,000 years.

Lake Arenal is an artificial lake in Costa Rica, located in the northern highlands of the country. It was enlarged to its present size as a part of a 1979 hydroelectric project by the Costa Rican government to provide electricity to the country. The lake is approximately 30 km long and almost 5 km at its widest point, making it the largest lake in Costa Rica at 85-square-kilometre (33 sq mi). It’s depth varies between 30 and 60 meters (100–200 feet) depending on the season.

The Town of Arenal was relocated to higher ground when the lake was expanded in 1979. The old towns of Arenal and Tonadora now lie abandoned at the bottom of the lake, with the new town of Arenal existing to the northeast on the lake.