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A Lower Carboniferous platform sedimentary sequence (the Paprotnia Beds) in the Bardo Unit of the central Sudetes (NE part of the Bohemian Massif, SW Poland) is biostratigraphically well dated, based on rich macro-and micro-fossil evidence, as Late Viséan (late Asbian, crenistria, Go III a zone). The beds contain several bentonite layers, one of which was dated using the U-Pb SHRIMP method on volcanic zircons and yielded an age of 334 ± 3 Ma. This date fits well to the recently established chronostratigraphic limits of the Viséan, and is consistent with the newest isotopic age constraints of 336.5-332 Ma for the Asbian boundaries.

The paper presents the results of geological and landscape studies in the Wojcieszów area (the Kaczawskie Mountains), which include investigation, inventory, documentation and a first evaluation of its geotourism objects. This area has high values of the natural environment and a rich geodiversity associated with a complicated geological structure (the Kaczawa unit, the metamorphic Kaczawa Complex). Some of the anthropogenic activities (mining), which have revealed interesting fragments of the geological structure, have also influenced the increase of geotourism attractions in this area. The area is one of the best examples of the region in the Sudetes, where economic considerations predominate over the protection of the natural environment. Since the 16 th century, the crystalline Wojcieszów limestone was mined in numerous quarries (e.g. Silesia, Gruszka, Połom, Miłek). In the limestone, intensive karst processes occurred mainly in the Paleogene (numerous caves and speleothems). As a result of economic activity, some of the caves had been permanently destroyed and the former "Połom" nature reserve was liquidated in the late 1970s. Currently, the only nature reserve is the "Góra Miłek in Wojcieszów". The area around Wojcieszów is rich in numerous quarries, where other construction materials were obtained (e.g. phyllites, greenschists, metarhyodacites). Since the 12th to 20th centuries, copper ore was also exploited (adits and shafts) in the Żeleźniak massif (east of Wojcieszów in the Radzimowice area). In the 20th century, uranium ore was sought at the Chmielarz Hill adit. Recently, the Cambrian limestones (Połom) and Quaternary deposits (Okrajnik, Stara Kraśnica) have been exploited. Paradoxically, economic activity, which caused destruction of some protected objects, has also enriched the geodiversity of the Wojcieszów region. The results of the evaluation proved the significant geotouristic potential of the studied area. The most attractive geosites around Wojcieszów demonstrate typical lithologies of the Kaczawa Succession and depict the pre-Variscan geological evolution of the area.

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