The pass of Cason di Lanza and the surrounding mountains were strategically very important, as the access to Carnia and the Friuli lowlands posed a direct threat to the Italians who therefore arranged an extensive system of defence lines and observation posts on the pass and the surrounding mountains. An equal situation was on Mt. Zermula too. It is still possible to see quite a few WW1 remains along the circular trail around the mountain: the inscription of the 35th Alpine Battalion Susa from 1916, partially demolished galleries below the ridge, observation posts, defensive walls, forts, remains of trenches, a chapel dedicated to the Susa Battalion. The top of Mt. Zermula, where a cross stands, offers a unique panoramic 360-degree view over the surrounding hills.
Exit A23 motorway for Pontebba and continue along SS13 towards the centre of Pontebba. After entering the village cross the bridge over the Pontebbana River and turn to Via Arturo Zardini (SP110). Follow the signposts for Studena Bassa‒Passo Cason di Lanza. You will reach the pass after 15 kilometres. Park there and continue on foot. The trail starts behind the abandoned cabin of the Financial Guard where trail CAI 442a begins. The trail leads to Forca di Lanza (1,831 m). At the first fork go straight and at the second one to the right. Follow the trail CAI 442. At the next intersection leave CAI 442 and turn right to Via delle Trincee (Trail of the Trenches). The trail will lead you past and through World War I remains to the top of Mt. Zermula. When descending from the top turn right to trail CAI 442 and follow it to the intersection you passed when going up. Continue along the same trail as you came up (CAI 442a) until you reach Passo Cason di Lanza.