The island, named Tofua, consists mainly of a massive ring-like caldera left by an explosive eruption millions of years ago. The caldera's steep walls stand up to 1,690 feet (515 meters) above sea ...

A 2022 satellite image shows smoke billowing from the caldera of Tofua, indicating an “imminent threat” from the volcanic island. A 2019 satellite photo shows the vanishing of Iceland’s ...