Mollusc assemblages found at the Wawel Hill in 2011 included 13 species; nine of the species found in 1988 were absent. Several shade-loving species had disappeared and some open-country species had increased in abundance at the expense of others. For example, Vallonia pulchella (Müll.) was a dominant component of the present malacofauna, while V. costata (Müll.) decreased in abundance. The results confirmed the environmental changes that had taken place since 1988: the negative impact of mass tourism and pollution.