Colo is a stratovolcano in Indonesia. It forms the small island of Una-Una at the middle of the Gulf of Tomini, the northern part of Sulawesi. The volcano is broad and has a low profile with only 507 metres (1,663 ft) above the sea level. It contains a 2 kilometres (1.2 mi) wide caldera with a small volcanic cone inside. Only three eruptions have been recorded in the history with two of them causing damage.

The eruption had a VEI of 3, qualifying as 'severe'. It involved:

• Central vent eruption
• Crater lake eruption(?)
• Explosive eruption
• Lahars

The island was evacuated, and there was damage to property.

This eruption was more violent and had a VEI of 4. It involved:

• Central vent eruption
• Explosive eruption
• Pyroclastic flow(s)
• Phreatic explosion

The island was evacuated, and there was damage to property, but there were no deaths.

• List of volcanoes in Indonesia