"Zwięzło" is a geological reserve with the area of 1.74 hectares situated on the slopes of Mt Chryszczata (Komańcza commune). Landslides are commonplace in the Carpathians. Landslide lakes form when rock material slides down into a river valley and dams a river flow. The reserve includes this type of lakes (created in 1907) called the Duszatyńskie Lakes as well as historic beech-fir forest.