Today we congratulate Yuri Sergeyevich Lyakhnitsky, Candidate of Geological and Mineralogical sciences, speleologist and leading specialist at the Karpinsky Institute, on his 80th birthday.

After graduating from the Leningrad Mining Institute, Yuri Sergeyevich worked at our Institute in Z.V. Sidorenko's group on mercury subject and E.I. Kutyrev's group on polymetals. He conducted fieldwork as a party leader in the Urals, the Yenissey Ridge, and Central Asia.

Then, in the 1990s, he was one of the initiators of the creation of the Sablino Nature Conservation and Excursion Centre, and also conducted research and monitoring of the Kapova Cave (Shulgan-Tash) in the Republic of Bashkortostan.

He developed passports for the Sablino and Staroladozhsky geological monuments of nature and 10 projects for excursion caves: Levoberezhnaya (in Sablino), Staroladozhskaya, Vorontsovskaya (in collaboration with the Sochi branch of the Russian Geographical Society), Kapova, Askyn (in Bashkiria), Monastyrskaya (near Mikhailovsky Monastery in Adygea), Bornukovskaya (in the Nizhny Novgorod Region), the Museum of Geology, Speleology and Mining (in a mine in the suburbs of Arzamas), and the Underground Route in the Ruskeala Mountain Park. He developed projects for an excursion and ecological trail in the Lava River Canyon and in Staraya Ladoga.

Yuri Sergeyevich is the author and co-author of 134 published works and 65 archival works. He has prepared a monograph entitled ‘Comprehensive Natural Science Study of Kapova Cave (Shulgan-Tash)’. He is the Сhairman of the Commission on Speleology and Karstology of the St. Petersburg branch of the Russian Geographical Society. He collaborates with the Leningrad Regional Non-Governmental Organization ‘Preservation of Nature and Cultural Heritage. Sablino’, the Natural-Historic Park ‘Shulgan-Tash Cave’ and the Shulgan-Tash State Nature Reserve.