Lake Pavin is today the second most visited site in the Sancy massif with 200,000 annuals visitors. As early as 1909, the commune of Besse-en-Chandesse created a path around the lake to encourage its frequentation. The general public was attracted by its mystery and reassured by the information provided by scientists. Indeed, in 1778, the road and bridge engineer Théodore Chevalier had sounded the lake and established a limit to its depth. From 1859 onwards, the introduction of trout, chars, salmons and crayfish, which survived, had cut short the legend of a poisoned lake.