The Julian Alps are rugged karst mountains located on the sunny side of the Alps not far from the Mediterranean, and are one of the wildest, untouched regions in Slovenia.

The Trenta Valley is the source of one of the most beautiful rivers in the Alps, the Soča in Slovenia, becoming the Isonzo in Italy - that flows from a mountain cave. In Trnovo the river flows into a narrow white-water gorge and large chunks of rock, the result of various earthquakes, lie on the riverbed.

Many tributaries feed the Soča, along with the Tolminka River whose sixty metre deep gorge can be seen from the Devil's Bridge. On a trail through the gorge are a variety of plants and insects which Dr. Julius Kugy, a mountaineer and writer, once recorded in meticulous detail.

It is believed that famous Italian poet, Dante Alighieri, once visited the Tolimka Canyons while staying in Tolmin and that the locality inspired his vision of the Underworld in his, Divina Comedia.

The largest stone railway bridge in the world crosses the pristine Soča which finally becomes, in Italy, the Isonzo River, situated within a delta in the Adriatic Sea.