The basin of the Mokra Volnovaha River, from the Mykolaivka village to the place where it flows into the Kalmius River, exposes an extremely informative geological cross-section of the conjunction of the Pryazov block of the Ukrainian Shield (US) with the complexly located Donetsk Hercynian structure. The results of the survey of this area are presented and the perspectives for creation of the MafHaia Geological Park named after the important paleo-volcanic structure are substantiated. The most significant events related to the geological studies of the regions from the academic expeditions of Pierre Guillaume Frédéric Le Play, P. S. Pallas to nowadays are considered in historic sequence. The structural-tectonic position of the territories, mineral-petrographic peculiarities of the rocks of the prospective geopark were studied and great geodiversity important for the development of the geotourism as an important component of functioning of geopark was determined. We followed sequential change in the geological cross-section from the association of Maksymivski granodiorites of the Middle Archean East-Pryazovska StructuralFormation Zones of the Ukrainian Shield in Mykolaivka village, terrigenous and volcanic formations of the Devonian system which are embedded on them and belong to the Eifelian, Givetian, Frasnian and Famennian stages, to terrigenous carbon-bearing deposits of Carboniferous system which form large rock outcrops on the Left Bank of the Styla water reservoir and outcrops in the quarries for extraction of flux limes and dolomites. It is proposed to consider as highly relevant the principally new “Balanced structural-geologic map of the Southern Donbass” proposed by V. V. Yudin, based on fracture-block tectonics, thrust faults which caused pre-fault mélanges and duplexes. The most characteristic peculiarities of the geological structure of the Rozdolne Geological Reserve as the main location of the future geopark were determined. As the one of the main attractions of geotourism itineraries, we evaluated the unique Devonian flora of global significance in the Velyka Karakuba (Rozdolne) village, particularly Archaeopteris archaetypus Schm., Archaeopteris fissilis Schm., Lepidodendron karakubense Schm., Demeripteris fasciculate Schm. and others, first in history discovered in 1894 by I. O. Shmal’gauzen. An important peculiarity of the zone of the junction of the US and the folded Donbas is its attractiveness for collecting minerals, including crystals and druse amethyst, smoky quartz, druses of pyrite, pseudomorph on corals, chalcedony, pseudo stalactites with marcasite, small agates, pink quartz, sanjuanite, fulgurite and others.