The origins of Montsec are well-documented in is cross-section and have been conserved for posterity in its rock face. Two hundred million years ago, the Montsec mountain range had formed part of a marine basin. With the passing of time, the forces of nature then combined to push, fold and raise these marine sediments and to give this area its present form. With its highest point at 1,676 metres above sea level, Montsec provides living evidence of how the passage of time and almost every step in a territory's history can be recorded in its physical geography.