The Cumbre Vieja volcano is located on the island of La Palma, just a few hundred metres off the shore of Tenerife and is part of an active, albeit currently dormant, volcanic ridge. It has erupted twice in the last seven decades, first in 1949 and then 1971, but over the last few years, thousands of tremors have rumbled from the giant, leading scientists to fear it could erupt in the future. Researchers say a volcanic eruption would not only cause devastation for the Canary Islands from the initial blast but could trigger a vast undersea landslide, too.