Live a whole day as a true explorer with a helmet and an electric torch to discover the depths of the earth in the Oliero caves, karstic caves located in the municipality of Valstagna, originated thousands of years ago by the force of the water.

There are four caves open to the public, surrounded by greenery in a natural park: from the two lower caves flows the River Oliero, while the two upper "covoli", ancient mouths from the same sources, are now dry. The visit to the cave park first follows a path that leads to the lane that leads to the Covolo degli assassini [Den of the Killers] Covolo delle sorelle [Den of the Sisters], dominated by towering rock walls. On those walls you can admire an abundant array of rock plants, from which the rock rampion stands out for its beauty. The trail then descends to the valley between the two main caves, completely surrounded by fresh spring water and immersed in the greenery of age-old trees. This opens the low wide mouth of the Siori Covolo or the Parolini Cave, named after the explorer who discovered it in 1822.

A visit by boat lasting about 30 minutes will allow you to discover all the secrets of this underground world, where a rare living fossil found refuge: the Proteus, an amphibious troglobite present only in the chambers of the Triestine and Slovenian Karst.

A particularly impressive spectacle is provided by the Sala della colata, a waterfall of alabaster stalactites, fourteen meters high, which enchants visitors with a variety of shapes and hues.