“…Three major mechanisms contribute to the formation of hyperacid environments: (1) the direct degassing of strong acids associated with magmatic activity in proximity of open conduit active volcanoes, often leading to the creation of hyperacidic volcanic lakes (Mapelli et al, 2015 ); (2) the biological oxidation of sulphide and other reduced sulphur species, which produces sulphuric acid as a byproduct (Colman et al, 2018 ), a key process in the development of hyperacid environments associated with geothermal systems, mine drainage, and the exposure of sulphide minerals to oxygen; and (3) the presence of high concentrations of CO 2 gases stemming from volcanic activity or other tectonic processes (Burton et al, 2013 ; Tamburello et al, 2018 ). The Mefite, located in the Ansanto Valley (southern Italy) is an example of the latter process given its extremely high concentrations of carbon dioxide along with the presence of non‐atmospheric nitrogen and hydrogen sulphide that are a consequence of tectonic processes (Chiodini et al, 2010 ), and it represents an exceptional site combining geology, archaeology, and biodiversity (Figure 1 ) (Sisto et al, 2020 ). Remarkably, Mefite represents one of the largest non‐volcanic gas emission areas, specifically a cold natural carbon dioxide spring, as depicted in Supplementary Video S1 by Di Iorio et al ( 2023 ), associated with sedimentary and tectonic phenomena (Chiodini et al, 2010 ; Pischiutta et al, 2013 ; Sisto et al, 2020 ).…”