Dernal Pass

Access

You can reach ISOLA DI CEVO from the Tonale and Mendola state road (SS No. 42):

* if you are coming from the valley (from Bergamo or Brescia) go up to Cedegolo and then turn right (the fork is immediately after the bottleneck in the centre of Cedegolo) onto the provincial road No. 6 for Fresine. After about 7 km uphill and then, after the cemetery of the hamlet of Fresine, take the little flat road on the right and in just over a km you will reach the hamlet of Isola: there are certainly no parking problems!
* If you are coming from the upper Valcamonica (Aprica or Tonale / Ponte di Legno), descend to the village of Cedegolo and then take provincial road 6.

Introduction

This excursion takes place in three characteristic and clearly distinct environmental situations:

1. the first section, as far as Lake Arno, the mule track climbs a steep wooded ridge for a difference in altitude of over 900 m where there is a transition from mixed coniferous forest, predominantly deciduous, to the final part almost completely covered with mountain shrubs.
2. The second is through a "building site road" partly in tunnels-paravalanche tunnels, which also passes close to the lake.
3. The third is the ascent up the "coster" on the orographic left, initially characterised by a few green alder bushes and only partially grassed, followed by a succession of mounded rocks and moraine accumulations.

From this ascent, the spectacle of admiring the entire basin of Lake Arno and Mount Campellio can be enjoyed. From a geological point of view, the Arno basin is particularly interesting because it is located in the contact zone between effusive rocks (Adamello pluton), metamorphosed schistose rocks and limestone.

Description

Starting from the small square in front of the church in Isola, go uphill, initially skirting part of the fence of the former hydroelectric power station (path [88]), then take the slope decisively, passing near two supports of a high-voltage power line; you will then reach the locality called "Il Plà", where there is a farmstead surrounded by a meadow carved out of the surrounding rocks. The path continues by crossing the site of the former forced conduits and the inclined plane of the power station with a small bridge; it then approaches the Rio Piz stream and passes near some supports of the former Isola-Arno cable car; the path continues with wide zigzags until it crosses the site of the former forced conduits again by means of a long bridge ("put lonc"). After a few hairpin bends, you reach the locality of Garzuné (approx. 1400 m), where a plateau can be glimpsed that was once the site of a malga, now completely ruined. We continue along a mule track with hairpin bends, then we move to the right (view from below) and follow a long stretch of path carved out of the rock of Monte Zucchello, until we reach the flat road, (formerly the site of the Decoville track), Vertice Q - Arno, signpost unable to parsen our left, we can see the buildings relating to the former Isola power station (the guardian's house, electric cabin, cable car and inclined plane etc.); we continue to the right. We walk along a stretch of road characterised by the presence of several tunnels and avalanche barriers in an artificial tunnel, until, on our left, a path branches off towards the top of the dam, which we reach in about 10 minutes. Once at the dam, we continue along the flat road to the Campellio power station; almost half of the road is in a tunnel or artificial avalanche parapet; until the 1970s it was equipped with a 'decoville' track and was used to transport materials from the Arno cableway to the power station. Along the way, we come across partially ruined buildings: where, in the past (until the 1950s), pumps were stored that were used to partially empty the natural reservoir of Lake Arno in winter; and thus also use the water below the level of the Isola power station intake. When you reach the Campellio power station, climb up to the left (path [89]), pass above the power station building, cross the penstocks and continue along the path to the Pozza d'Arno. In view of the Pozza d'Arno, keep to the right and climb up the slope following the path marked with [89] (turn left, cross the little valley and continue diagonally); at an altitude of around 2400 m, on the spur which, near the deep incision formed by the Val Ghilarda delimits it, when you are already in view of the Dernal pass, join path [1] coming from the Campo pass. From Pozza d'Arno to the hut, the average walking time is about two hours. If you want to go round the Arno basin, the return can be made via path [1] to the Campo pass, then along the Traversera path (signpost [20]) to the crossroads above the Arno reservoir dam, then path [20] to the dam and then the same route up to Isola.