The El Soplao Cave is located between the towns of Valdáliga, Herrerías and Rionansa. It was discovered in the early 20th century during the mining exploitation of La Florida. It is located in an area of high natural and panoramic value, with forests and varied wildlife, remains of mining archaeology and views out to the Cantabrian Sea, the towns of Comillas and San Vicente de la Barquera and to the Picos de Europa. The cave is considered to be one of the world’s geological wonders, as it is a cathedral of stalactites and stalagmites that grow into unique formations.