The most important passes are Niska - 410 meters high and Križić 371 meter high. 639-meter high Sis is a top on the ridge of Cres where prehistoric buildings are located: these buildings served as a strategy fortress because of its view over the whole bay of Rijeka. The pass Križić was also of major traffic importance as the sea from both sides of the island can be viewed from this spot. Climb Sis has been a long hiking tradition. The climb begins at the pass Križić at the crossroads of the main island road and branch-road to Beli. A visible path leads through the ridge along a dry stone wall, it is levelled and easy to orientate and provides a breath-taking view over the surroundings and the sea.
In spite of its significant height Sis is not the highest peak on Cres. The top Gorice is 648 meters high and is the second highest island peak in Croatia. It is located some 2 km to the north of Sis; however, it is not that popular among hikers as there is no marked path or view.