Monti Simbruini and Ernici

The Monti Simbruini and the Monti Ernici, like all the mountains of the Apennines, run from north-west to south-east.
They are two mountain complexes forming a single chain that closes off the Valle del Sacco to the north-east and marks the border between the regions of Lazio and Abruzzo.
The mountains of these two groups are made of Cretaceous limestone interbedded with conglomerates, which are also calcareous. The highest summit of the Monti Simbruini is Monte Viglio (2156 m), and they are separated by a great fault from the nearby Monti Ernici. The latter, also made of rocks from the Jurassic and Cretaceous periods, show the karst erosion features of the nearby Abruzzo mountains.

The Monti Simbruini take their name from the Latin "sub imbrimus", which means "under the rain". They are mountains extremely rich in water and, for this reason, in vegetation. This makes them especially well suited to summer hikes. The beech woods covering every slope of these mountains are beautiful, in particular the beech wood you walk through to reach the Santuario della SS. Trinità from Vallepietra.

The Monti Ernici are very similar to the nearby Simbruini: they too are in fact covered by thick woods of tall beeches. In this area, as around Vallepietra, besides ravens many birds of prey such as falcons and eagles nest. A by now small population of wolves lives in these forests.
The most important mountain complex of this group is formed by the summits of Pizzo Deta, Monte Passeggio and the lesser peaks around the great valley of Prato di Campoli.