U skal

U skal is a small but scientifically remarkable nature monument lying southwest of the village of Vyšehořovice, near Kozovazy, in the Praha-východ district of the Central Bohemian Region. The protected area covers just under 6 hectares at an elevation of 230 to 241 metres above sea level. It received official nature-monument status on 1 December 1986, declared by the former Praha-východ district national committee.

Why is this site protected?

The reason for protection has nothing to do with dramatic scenery — it lies in what the rock layers of former quarries hold beneath the surface. Dark, coal-rich claystones from the Upper Cretaceous preserve an exceptionally rare, internationally recognised assemblage of fossil plants. It is precisely this paleontological value that led to the site's legal protection.

What was found in the old quarries?

Local sandstone was quarried here as late as the 18th century, supplying material for church buildings in nearby Nehvizdy and Vyšehořovice. Quarrying, however, exposed something far more valuable than building stone: Cenomanian-age layers of the Upper Cretaceous containing imprints and remains of plants tens of millions of years old. Researchers Edvín Bayer and Josef Velenovský identified nearly 80 Cenomanian plant species at the site, including conifers such as Araucaria, Sequoia and Cunninghamia, tree ferns, and magnolias. Palaeontologist Antonín Frič additionally documented insects and freshwater mussels found here. This diversity gave the locality lasting renown among palaeobotanists worldwide.

What does the site look like today?

The originally bare, exposed quarry faces have gradually become overgrown with volunteer tree growth that established itself without human planting. Alongside ruderal species, plants typical of oak woodland now thrive here, and large stretches of the ground are covered in extensive moss growth. Birds such as hawks, woodpeckers and warblers can be found among the trees, and the area also shelters small mammals.

Who manages the reserve?

The site is administered by the Central Bohemian Regional Authority. Because its protection is scientific in nature — focused on geological strata and fossils rather than tourist infrastructure — U skal remains a quiet locality, visited mainly by those interested in geology and the region's natural history.

Frequently asked questions

Where exactly is U skal located? Southwest of Vyšehořovice, near the village of Kozovazy, in the Praha-východ district of the Central Bohemian Region.

Since when has the area been protected? Since 1 December 1986, when it was declared a nature monument.

What makes this site special? An assemblage of Upper Cretaceous (Cenomanian) plant fossils preserved in former quarries, comprising nearly 80 identified species, including conifers, tree ferns and magnolias.

Is the site wooded? Yes — although the quarry faces were originally bare, the area is now covered by tree growth that appeared spontaneously, without deliberate planting.

Can fossils be collected there? No. The area holds legal protection as a nature monument, so disturbing the geological layers or removing fossils without the administrator's permission is not allowed.