DeepWalls utilises advanced imaging technology and software processing to achieve the projects objectives. We have demonstrated that vertical walls host an abundance of life, including important reef-forming, and habitat-building cold-water coral species. Glass sponges and reef-building scleractinian corals were found on the vertical walls, which provide a 3D skeletal framework that increases the structural complexity of the habitat and likely enhances biodiversity at the local scale. Large black corals were observed, protruding over a metre from the walls, providing habitat for abundant associated fauna. We have utilised innovative and complex computer algorithms to quantify the wall in 3D images, observing a plethora of geomorphic features, which contribute to generate a rich and heterogeneous habitat.

1. Deep-sea discoveries: the Azores region hosts several deep-sea walls, ranging from small cliffs to large vertical walls.
2. The verticals walls evaluated were mostly very steep (>70 degrees) and formed of basalt rock. Where basalt rock formed pillow lava, large heterogeneity was observed, including small overhangs, bulbous outcrops and flat surfaces where sediment would settle. This complexity created a fragmented habitat with potentially many ecological niches at scales of several metres.
3. Deep-sea walls around the Azores are home to a variety of important habitat-forming species such as black corals, gorgonians, reef-forming cold-water corals, oysters, glass sponges and crinoids. These species contribute to the structural complexity of the walls, with potential implications for local biodiversity metrics.
4. Underwater images revealed the capacity of black corals to harbour a high number of associated invertebrate species, including sessile (e.g. anemones, molluscs, hydrozoans) and free living (e.g. crustaceans). In some areas, black corals also harboured the eggs of deep-sea sharks, indicating the importance of such communities, not only as refuge and feeding areas for associated fauna, but also as potential nurseries for some rare or sensitive species.
5. High abundance of black corals, sponges, cold-water scleractinian corals (which are considered VME indicators), may indicate that underwater deep-sea walls act as VMEs due to enhanced structural complexity, presence of long-lived species and their rarity.
6. Several black corals measured over 1 m, which would suggest hundreds of years of growth, likely uninterrupted from physical impacts due to their pristine appearance. The walls may act as refugia to sensitive species, providing physical protection from example, from fishing activities.