Cueva de los Verdes

Cueva de los Verdes is a lava tube and tourist attraction. The cave was created around 3,000 years ago by lava flows erupted from the nearby volcano Monte Corona, flowing across the Malpaís de la Corona toward the sea. The cave is also famous for its concert hall which is located near the entrance and exit of the cave. The concert hall has about 15 to 20 rows with 26 seats in each row, allowing up to 500 people in the concert hall at once. -from Wikipedia