Gruta de Lourdes

Located 17 Km. (10 mi) from the city, it is a beautiful sanctuary built in 1947 and visited since then both by believers and non-believers for its particular appeal. You should first drive 14 Km. (8.5 mi) along national route 281, which is paved and is the access to the city, and then turn off on a gravel road and continue for 3 Km (2 mi). 
It is located in the Cañadón de las Bandurrias, a wide gully leading to the ria, with 20-meter (66 ft) walls. The cave stretches out across a volcanic massif formed more than 150 million years ago.