The “Strada del Ferro” or “Maria Teresa Road” was in the past centuries an important communication route particularly linked, as the name clearly indicates, to the extraction of ferrous minerals. It started from the Giabi di Premana hamlet and went up the entire Val Varrone culminating at the Bocchetta di Trona. It was traced many centuries ago to transport iron ore mined in the basin of the upper Val Varrone downstream. Looking from the pass towards the Val Varrone, just below, on the left, you can still see a small hut near the former iron mines. Through this easy pass, the road then connected with the mining system of the upper Val Gerola.
AloJapan.com