Research in caves is rare and restricted to speleological explorations. Picos de Europa Massif shows a spectacular development of vertical caves deeper than 500 m. Torca Teyera is a 738 m-deep and 4 km-long vertical cave. The aim of this work is to establish a methodology to characterize the geological and geomorphological aspects of this special group of caves, as well as to identify the factors conditioning karst development. The research involves (1) the cave survey at a 1:500 scale and the construction of a 3D model, (2) the geomorphological mapping on the topographical survey, (3) the geological mapping of the cave environment at 1:5000 and (4) the comparison in stereographic projection of the obtained survey data and joint measures.