Ponga Natural Park is situated in the Ponga Geological Unitof the Cantabrian Zone. The principal rock in the park is limestone, with areas of slate and sand stone in the valleys.

The most notable geological features are the limestone fins or ridges, which wind across the landscape, and are due to tilting, over thrusting, and faulting of the rock strata, with folding at right angles to thefault-lines.

These fins may be tilted up to the vertical, and can actas barriers when crossing the terrain.

The distinctive mountain summits within the park are results of these geological processes -crests with a vertical rock face on one side and a relatively gentle gradient on the other - as typified by Tiatordos, La Llambria, and El Recuencu.