“Blasted into existence by quarrying in the early 2000s, this line was shaped by human intervention—but its beauty was pure chance. When the late Adriano Trombetta and Marzio Nardi bolted it, they couldn’t have predicted that the rock fractures from mining would create something so striking. Pioneers of the Torino climbing scene and its surrounding valleys since the early ’90s, Adriano and especially Marzio have left a deep mark on Italian climbing development. Yet this route—right beside the road in one of Italy’s top climbing areas—remained unclimbed for over two decades, despite attempts by some of the country’s strongest. Drawn to the unusual, James Pearson sets out to unlock the “Diamante Grezzo” — and discovers why it means so much to Marzio.”