During autumn, winter and spring it exists as a well, while during the summer months it takes the form of a sink-hole. It is located on the right side of the River Sušica stream, below the steep sides of Viroštak (1119m). It is of elliptic shape, whose longer axis in the form of well is 127m, while the shorter one is 85m. During the highest water levels, a depth of 56 metres was measured.

During the period in which the estavela starts to function as a well, generally after heavier rains in the area of Duga and Golija, underground waters usually suppress the air from the cavities, causing "bursting" on the estavela accompanied by a eruption of fine dolomite sand. After that, the water withdraws abruptly, taking the place of the underground air, the water level rises and the estavela continues to function as a well.