Kone, also called Gariboldi, is made up of seven nested calderas, lava flows and basaltic cinder cones.

The normal faults cause magma to rise inducing the volcanic activity.

There are many rock types identified at Kone and they are divided into five main groups, trachytes, comenditic rhyolites, ignimbrites, pumices, syenite inclusions and basalts.

The ignimbrites have formed massive green sheets ranging in thickness from 15 cm to 25 m. The pumice deposits over the ground are common within Kone's Volcanic Complex and range in thickness from 50 cm to 20 m. Most of the pumice is found interlocked with the ignimbrites.

The story tells about an engineer who was responsible for building a road through two of the collapsed calderas, thereby connecting Addis Ababa to Djibouti during the 1940s.