Troggia Falls or Cascate della Troggia is a waterfall on the Lake Como in Introbio, near Lierna.

Landscape with a river by Leonardo really refers to the narrow landscape that connects Lecco with the upper Valtellina, a territory under the dominion of the Sforza of Milan

• Invalsasina infra Vimognio et Introbbio amandesstra entrando per la via di Leccho si trova la Trosa fiume che chade da un sasso altissimo e chadendo entra sotto terra elli finisscie il fiume. (Modern Italian)
  • In Valssasina between Vimogno and Introbio on the right as you enter via di Lecco is the Troggia river which falls from a very high stone and as it falls it enters the ground where the river ends (referring to the surroundings of Troggia Falls or Cascate della Troggia on Lake Como in the mountain of Grigne).
    • Leonardo da Vinci