In the Alps, trench warfare even stretched onto vertical slopes and deep into the mountains, to heights of above sea level. The Ortler had an artillery position on its summit near the front line. The trench-line management and trench profiles had to be adapted to the rough terrain, hard rock, and harsh weather conditions. Many trench systems were constructed within glaciers such as the Adamello-Presanella group or the famous city below the ice on the Marmolada in the Dolomites.