Of Indonesia's many active volcanoes, the most active (and potentially the most dangerous) is Mt. Merapi. It is situated near the middle of the island of Java, on the border between the provinces of Cenral Java and Yogyakarta. With a peak elevation of just under 3k meters above sea level (around 9.7k ft.), the volcano has been erupting regularly for over 400 years. As of 2019, it's one of 16 Decade Volcanoes thought to be the world's most dangerous. You can check it out from a bird's eye in this drone video by drone_ulun.