Les Grottes Pétrifiantes de Savonnières, also known by John Evelyn as the “Gouttières”, are two grottoes located in Savonnières, Indre-et-Loire, France. The grottoes were mostly formed during the Middle Ages, the stone (tuffeau) being used to build châteaux. Centuries later, the caves were flooded with water, slowly creating new passages. They were visited by Bernard Palissy in 1547, and an extension (the second grotto) was discovered by a speleologist (Gilles) in 1947.
“Petrified” plants Objects are put under the grottoes’ springs for six months to a year, which covers them in limestone, creating a “petrified” look.