540 km Radmarathon in Norwegen von Trondheim nach Oslo.
Den Store Styrkeprøven (English: The Great Trial of Strength, Deutsch: Die Große Kraftprobe) is a 540 km long bicycle cyclosportive in Norway, which starts in Trondheim and finishes in Oslo. It was first held in 1967 and has taken place since then in late June every year.
