Porezen, Mountain summit in northwestern Slovenia.

Porezen is the highest summit of the Slovenian Prealps, reaching 1,630 metres. Its southern and western slopes are rich in mountain flowers, while the northern and eastern sides are forested. The summit holds remains of a labyrinth of underground tunnels linking fortifications of the Italian Vallo Alpino, built before World War II.

During World War II, military fortifications and bunkers were built on the slopes as strategic positions. Remains of these structures are still visible across the mountainside today.

The summit carries a monument to the battle of 24–25 March 1945, when 36 members of the Kosovel Brigade, the Gorenjska war area, the engineering battalion of the XXXI Division and other Partisan groups fell fighting part of the 14th SS Police Regiment; 145 (some sources say 106) were captured and executed. The name Porezen is used for the highest point of the Cerkljansko hills.

Several marked hiking trails lead to the summit from different starting points such as Cerkno, Davča, and Petrovo Brdo. Most hikes take between three and five hours depending on which route is chosen.

At the summit stand the remains of a labyrinth of underground tunnels linking fortifications on the northern and eastern sides, built by Italy before World War II as part of the Alpine Wall (Vallo Alpino) on the border with the Kingdom of Yugoslavia.