Croatia does not really have the most exciting geology. With several unusual spots, the country is mostly made up of karst. That’s why Stara Straža geological monument is so special and unusual in this region.
Karst Geology of Croatia
Croatia is mostly made up of limestone and dolomite sedimentary rocks that were formed some 250 mil to 65 mil years while most of the country was under the sea. Tectonic processes have risen the modern day mountains and the rest was done by the weather. That is what karst is: landscape underlain by limestone which has been eroded by dissolution, producing ridges, towers, fissures, sinkholes and other characteristic land forms. It is common in this part of the world. The oldest geological structures in Croatia originate from Paleozoic and are between 541 – 245 mil. years old.
Stara Straža Geological Monument
Stara straža is located near Knin. There is a sign “Stara straža” on one of the curves on the road and an easy turn left if going to Knin. Hard to miss. The sign and this geological monuments are less than a minute away from the turn.
The site is best known for its swirly formations in the rock.
The Stara straža site is covering an area of just a bout 1 hectare and it was protected in 1961. The best known feature is visible wave in the rock, about 15 m wide and 5 m high, representing the waving bending of layers of the Earth’s core.
The wrinkled layers were formed under the influence of pressures following the movement of the rock mass. This site originates from Jurassic and Cretaceous age (201 mil to 66 mil years ago) . It is composed of alternating limestone and dolomite rock, with zones of grey limestone and horn stone.
Aparently, the coral Cladocoropsis is easily visible but you probably have to know what to look for. Unlike me. But I enjoyed various little rocks.
This Stara straža site is important for its characteristic profiles for various geological niches: paleontology, mineralogy, petrography and sedimentology. The profile is used to educate people on various layers of our planet.
Stara straža site makes an interesting stop when in the area!
More on the site: https://www.tz-knin.hr/en/explore/natural-heritage/stara-straza/