Here we can observe a contact between two kinds of different metamorphic rocks, i.e. rocks that during their forming went through changes due to huge variations in compression and intense heat. The large boulder that appears on the right of the bridge, (of a reddish colour) of untidily compacted paragneiss (Gneiss of Stabbiello), meets hornblende and epidote schist (grey) along the edge of the stream. These metamorphic rocks are very old, going back more than 280 million years (Permian).
In the surrounding wood grow the Sycamore, Wild Lime, Common Ash, Chestnut, and the Locust tree. Behind the emerging rock, grows a Medlar. Due to its humidity and the particular freshness, this is an area rich in ferns. Of special interest among the different species to be found in the dry-wall behind the mill, is the Soft shield-fern. This plant is protected by Federal law and is registered in the "Red List". We also find the Wall rue, the Common Polypody, the Scaly fern, the Male fern, and the Lady fern.
Wild boars regularly visit this area, as can be seen from the many holes in the ground made by these animals when rooting for food: acorns, roots, bulbs, insects, and worms. The wild boars' digging habits are beneficial to the wood's ground. After disappearing from Ticino for more than two centuries the wild boar reappeared in the Malcantone in 1981 and has now repopulated our woods.
The Historical Sonvico Nature Trail
Stage 1: Well and "Riaron"
Stage 2: House of Reason
Stage 3: Graad
Stage 4: Cassinel
Stage 5: The mixed broadleaf woods
Stage 7: Mill and bridge
Stage 8: The glade in the wood
Stage 9: The torrent Franscinone
Stage 10: Wash-house
Stage 11: The birds of the wood
Stage 12: The eroded valley of the Franscinone
Stage 12: Water and energy
Stage 13: The edge of the flood-level wood
Stage 14: Dairy farm for the processing of milk
Stage 15: Lime-kiln
Stage 16: The rural area
Stage 17: The Humid area of Canéed
Stage 18: The earth kiln for charcoal production
Stage 19: Terracing
Stage 20: Madonna d'Arla
Stage 21: The Chestnut Wood of Pian Piret
Stage 22: The Beechwood
Stage 23: The Boulder with Engraved Cupels
Stage 23: I Denti della Vecchia
Stage 24: R’Alborón
Stage 25: The Oratory of S. Martino
Stage 26: The old center of Sonvico
Stage 27: The Walnut Press
Stage 28: The Church of Saint John the Baptist
The Luganese Regional Bus Line covers the Lugano – Sonvico stretch; from Val Colla you can reach Sonvico, using the postal bus from Tesserete to Sonvico.