Geoinformation spatial analysis of the availability of natural heritage sites in a 100-km zone around Nizhny Novgorod (Russia)Anna Demyanchuk, Andrej Astashin, Galina Kamerilova, Ol'ga Vatina and Valeriya PodkovyrinaE3S Web Conf., 623 (2025) 01013DOI: https://doi.org/10.1051/e3sconf/202562301013