Assessment of microbial communities colonizing the Azé prehistoric cave

•Biofilms were assessed inside and outside the Azé prehistorical cave.•Several vestiges remain in the cavity and are colonized by microorganisms.•Each section of the cave host different bacterial or phototrophic communities.•The microbial richness decreases from the outside to the bottom of the cave.•The outside environment is the main driver of the cave communities.