(CNN) With Indonesia, the question is not whether an earthquake will occur but when. Indonesia is prone to earthquakes because it's on the Ring of Fire , an arc of volcanoes and fault lines in the basin of the Pacific Ocean. The area shaped like a shoe spans 40,000 kilometers (25,000 miles) and is where a majority of the world's earthquakes occur. In recent months, the Indonesian archipelago has been hammered by earthquakes, a deadly reminder of the islands' dangerous location. The main earthquakes are followed by dozens of aftershocks that continue for days.

Source: CNN September 29, 2018 12:11 UTC