21.15109/CONCORDA/XRLKLY Hatvani, István Gábor0000-0002-9262-7315(HUN-REN Research Centre for Astronomy and Earth Sciences)Kern, Zoltán0000-0003-4900-2587(HUN-REN Research Centre for Astronomy and Earth Sciences)Czuppon, György(HUN-REN Research Centre for Astronomy and Earth Sciences)Reitmeyer, Bence(HUN-REN Research Centre for Astronomy and Earth Sciences) ARP 2026 hdl:21.15109/CONCORDA/XRLKLY/VQDUSN The dataset is the foundation of the first isoscape of Hungary from stable isotope samples collected from subsurface waters. The resulting series of maps not only carries new interesting information for society about the stable isotopic composition of underground waters but can also serve as a reference for further research, such as determining the mixing of underground waters, the spread of pollutants, etc. because waters of different origins have unique stable isotopic compositions, which serve as their fingerprint properties. The current version (v1) holds data for 2023 and 2024, it will be updated with sites and time points continuously. Hatvani, István Gábor(Research Centre for Astronomy and Earth Sciences)Hatvani, István Gábor(HUN-REN Research Centre for Astronomy and Earth Sciences)