A kind of natural hydro-geological monument can be found in the centre of Ogulin. The River Dobra ends its normal flow here and disappears underground through the canyon in the middle of the town. It sinks into an enormous chasm – Đula’s Abyss – continuing with the Medvedica cave, the longest cave example in Croatia. 15,701 metres of this geological system have been investigated so far.
As stated above, the name of this abyss is connected with the legend about Đula and her unhappy love.
It is a curious sensation when one imagines how the biggest area of this town lives above the most beautiful natural figures that water can create in the karst.
Some of the steep stone face of the chasm is a challenge to alpinists to try their knowledge and skill there.