In the town of Otruševec near Samobor there is one of the most beautiful caves in northwestern Croatia - Grgos Cave. It was discovered by chance in 1973 by Josip Grgos while digging and blasting the stone he used to produce lime, and a year later it was protected as a geomorphological monument of nature.
Thirty years later, during work on expanding the reception area, the entrance to another cave, known as the "New Grgos Cave", was discovered. The cave has been arranged for visits since 2008. Both caves are relatively small, but due to the exceptional richness of cave decorations, they are a tourist attraction and are a recognizable part of geoheritage. Zagreb County. This cave is an unavoidable attraction for every visitor to the picturesque Samobor.
In just an hour and a half easy walks along a two-kilometer long path, passing through nine diverse points, you will get to know the life, customs and legends of the Otruševec area, from the underground beauties found in the Grgos cave, through geological and biological specifics to stories about ancient giants and hardworking people of the Samobor region.
Natural values
The total length of the old cave is 52 meters, and the depth compared to the entrance level is 19 meters, while the length of the new cave is 97 meters, and the depth is 14 meters.
According to very thick sigma clusters and stalagmites on the ground, it is possible to conclude that the cave is relatively old, while the multitude of thin stalactites on the ceiling indicates the still existing process of creating and shaping the cave space.
The special value of the caves are numerous whitefish of different species. Grgosov's cave is decorated with pipes or macaroni, eccentric sigas and curtains or draperies. Each new drop leaves a mark and so the curtains become longer and longer.
Grgos Cave hides great biodiversity
According to the analysis of smoke from the cave, it was found that it consists of 95% calcium carbonate and 5% aluminosilicate. The whitefish in the cave are of different colors – white, pale yellow, yellow, orange and brown. The color of the smoke depends on mineral admixtures, the soil above the cave, plant cover and the state of the environment.
So far, two whitefish from the new Grgos Cave have been analyzed, their age and the climatic conditions that once prevailed. One stalactite began to grow 10 years ago and stopped growing about 500 years ago. During the growth period, it grew at a rate of 2 to 300 centimeter in 0,8 years or 1 to 100 millimeter per year. The oldest part of the second stalagmite is about 0,08 years old with a change in growth rate of 0,1 to 40 centimeter in 000 years.
/ / /If you haven't already, go on a trip to Samobor
As many as nine groups of invertebrates live in Grgos Cave. Croatia is a global focus of biodiversity in terms of the richness of subterranean species, and many species that inhabit the Croatian subterranean are endemic to Croatia or the Dinarides.
Source: Zagreb County Green Ring Public Institution, Zagreb County Tourist Board
