Mycological surveys of the Yalguba Ridge, a unique natural feature composed of volcanics (variolites) formed ca. 2 Ga BP, were carried out in 2021 and in 2023-2024. Being situated in the vicinity of Lake Onego, this locality is esthetically appealing, while easy access from Petrozavodsk and lakeshore infrastructure turn it into a recreational destination. Records from our surveys and previously available data total 293 agaricoid, aphyllophoroid, and gasteriod basidiomycete species of 162 genera, and 6 ascomycete species of 6 genera. Specimens for some species are available in the Herbarium of the Karelian Research Centre RAS (PTZ). New localities have been identified for 14 species red-listed in the Republic of Karelia (Clavariadelphus pistillaris, Cortinarius sanguineus, С. violaceus, Cystodermella cinnabarina, Elmerina caryae, Gloiodon strigosus, Hygrophorus erubescens, Lentaria afflata, Leptoporus mollis, Meripilus crocatus, Pholiota squarrosa, Picipes badius, Stropharia aeruginosa, Tomentella crinalis). This site has yielded Karelia's first record of Chlorencoelia versiformis, and in 2023 Thelephora caryophyllea was encountered, constituting a third record for Karelia. Eighteen of the fungi are indicator species of biologically valuable forests, and 13 species are specialists of such ecosystems. Dead fallen and standing trunks and stumps carried a total of 166 species. The saprotrophic group includes 15 humus-dwelling species, 34 species inhabiting the forest floor, and 4 species living on litterfall; 83 species are mycorrhizal fungi. These results prove the forest site in this recreational green area is of high biological value and provide rationale for nominating it as a protected area.