Iliboleng, Stratovolcano on Adonara Island, Indonesia.

Iliboleng is a stratovolcano on Adonara Island with steep slopes made of basalt rock. The mountain's structure was built up over time through repeated eruptions that layered volcanic material on top of one another.

The first recorded eruption of Iliboleng took place in 1885, consisting of moderate explosions. An eruption accompanied by lava was recorded in 1888, and the volcano's last recorded eruption dates to 1885 in Indonesian records. Its activity is classified as moderate.

The volcano's summit holds several craters, named K1 to K5 with K5 as the main crater, plus a separate crater called Riawale. These names come from the local Indonesian record of the mountain and are the terms used for its summit features.

Iliboleng sits at the southeastern end of Adonara Island, in the Larantuka area of East Flores Regency, East Nusa Tenggara. The usual approach is by ferry from Larantuka to Adonara, then overland to the villages below the mountain; from there, local paths lead up. Arrange a local guide for route-finding, and check conditions before setting out.

The summit is not a single crater but a cluster of several, labelled K1 to K5, with K5 as the main crater; a separate crater called Riawale also sits on the mountain. The 1888 eruption was the one recorded as producing lava flows, not just explosions.