The unique rock formation on the Bale plateau was created millions of years ago from lava outpourings.

The Bale highlands consist of a vast lava plateau with at least six volcanic cones, each more than 4200 m high. These cones have been flattened by repeated glaciations.

The endemic giant lobelia (Lobelia rhyncopetalum), which stands up to 10 m high including its inflorescence, is scattered across the landscape up to the highest altitudes of Tullu Deemtu at 4377 m.