Dallol is a cinder cone volcano in the Danakil Depression, northeast of the Erta Ale Range in Ethiopia. It was formed by the intrusion of basaltic magma into Miocene salt deposits and subsequent hydrothermal activity. Phreatic eruptions took place here in 1926, forming Dallol Volcano; numerous other eruption craters dot the salt flats nearby. These craters are the lowest known subaerial volcanic vents in the world, at 45 m (150 ft) or more below sea level. In October 2004 the shallow magma chamber beneath Dallol deflated and fed a magma intrusion southwards beneath the rift. A phreatic eruption occurred in January 2011.

Numerous hot springs discharge brine and acidic liquid here. Small, widespread, temporary geysers produce cones of salt. The Dallol deposits include significant bodies of potash found directly at the surface.

The term Dallol was coined by the Afar people and means dissolution or disintegration, describing a landscape of green acid ponds (pH-values less than 1) and iron oxide, sulfur and salt desert plains. The area resembles the hot springs areas of Yellowstone Park.