The Canary Islands not only boast the third largest volcano in the world, but also the largest natural underwater lava tunnel.

Mount Teide, the third largest volcano, resides in Tenerife, while the colossal La Corona volcanic tube is found in Lanzarote.

Formed over 20,000 years ago following the eruption of the Corona Volcano in northern Lanzarote, this impressive tube stretches approximately 4.7 miles, with nearly a mile submerged underwater.

Recently, the volcanic tube has been proposed as a new World Geological Heritage Site by the Commission on Geological Heritage of the International Union of Geological Sciences (IUGS).

The tube is an intriguing labyrinth of interconnected corridors and galleries featuring expansive vaults, small interior lakes, and a blend of dry and submerged cave sections.

The three notable parts of the tube are Cueva de los Verdes, Jameos del Agua, and the Atlantis Tube. 

Cueva de los Verdes and Jameos del Agua located inside the volcanic tunnel, are natural caves that are open to visitors and natural caves that were formed following the eruption of the Corona Volcano.  

Cueva de los Verdes, which means "Cave of the Greens" is known for its captivating shapes and vibrant colours, beautifully formed in the volcanic rock.

Some say that the "Green" refers to the green hues reflected in the natural rock formations inside the cave, while others believe that it was the secret hideout of a wealthy family known as Los Verdes. 

The journey through the cave culminates in an auditorium known for its spectacular natural acoustics. 

The Jameos del Agua ("Caves of Water") is the section of the tunnel that is the closest to the coast and owe their name to the underground lake, which is home to an endemic species of blind and albino crab. 

The site also features the 'Casa de los Volcanes' geological museum, exhibition spaces, a multifunctional room, and even a concert hall.

The Atlantis Tube is the part of the tunnel that remains submerged below sea level.