Erlengarria XI

The mouth of the cavity is wide, presenting a height of around 2.5 metres, with 1 metre of width. During the first metres of development, this gallery presents a meandering morphology, giving onto some metre-sized clasts that slightly hinder progression. This gallery ends after 8 metres of horizontal development in a descending zone ending in a small chamber, which presents two possible continuations. On the left, after making a somewhat delicate passage, there is a narrow, sinuous meander, which although it continues, has not been forced more than 5 metres. If, avoiding this, one continues along the main gallery, one reaches a wider zone after descending a vertical step 2 metres deep. Beneath this step a hidden gallery then appears in the form of a narrow, ascending meander. Once one has returned to the main gallery, a more phreatic morphology is observed, with intense cavitational forms evident on its walls and ceilings. The floor is strewn with small clasts with semi-sharp edges, which show a thin layer of decalcification clay on their faces. After a slight turn to the left, an unreachable phreatic tube is observed in the upper part of the gallery. Ascending a phreatic ramp formed by semi-dehydrated lutites, one reaches a new gallery that crosses the main one perpendicularly. On the left side there is, after ascending a small step 0.8 metres high formed by wedged clasts, a gallery of little development, which ends in a clastic plug with abundant beech leaves, evidencing an obstructed exit to the exterior. The right zone shows limestone floors and somewhat greater width in its section, continuing as a phreatic tube, to end in a limestone unblocking a few metres into its development. In the middle zone of this gallery, next to some clasts of centimetric and decimetric size, there is a very greasy and hydrated clay deposit formed by phyllosilicates from degradation.

Flowstone is abundant in this zone, progressively narrowing the gallery until it ends in a small impassable crawlway.

Beneath this step a hidden gallery appears in the form of a narrow, ascending meander, which usually provides a meagre flow in times of heavy rainfall.