The Ancient peoples of pre-Roman Italy – such as the Umbrians, the Latins (from which the Romans emerged), Volsci, Oscans, Samnites, Sabines, the Celts, the Ligures, the Veneti, the Iapygians, and many others – were Indo-European peoples, most of them specifically of the Italic group. The main historic peoples of possible non-Indo-European or pre-Indo-European heritage include the Etruscans of central and northern Italy, the Elymians and the Sicani in Sicily, and the prehistoric Sardinians, who gave birth to the Nuragic civilisation. Other ancient populations being of undetermined language families and of possible non-Indo-European origin include the Rhaetian people and Cammuni, known for their rock carvings in Valcamonica, the largest collections of prehistoric petroglyphs in the world. A well-preserved natural mummy known as Ötzi the Iceman, determined to be 5,000 years old (between 3400 and 3100 BCE, Copper Age), was discovered in the Similaun glacier of South Tyrol in 1991.