Clelia Campolongo was born in the comune of Laino Borgo in the province of Cosenza in the Calabria region of southern Italy, on 9 January 1906. She was the eldest of ten siblings, and only one—twenty years her junior—survived her. In 1931, she married Rinaldo Zanetti in Rome, and together they had three daughters. Shortly after their wedding, they moved to Umbria, and by 1933 they had settled in Terni, where she would spend most of her later years, living with her daughter Floriana and son-in-law Amedeo.
Clelia Campolongo passed away in Terni, Umbria, Italy, on 2 March 2016, at the age of 110 years, 53 days.
In January 2016, she celebrated her 110th birthday, becoming the second known supercentenarian from the region of Umbria, after Dante Parlani. She also held the title of the region’s oldest woman ever until 21 November 2020, when her final age was surpassed by Maria Saldi.
Campolongo’s age was verified by Alessandro Delucchi and validated by the European Supercentenarian Organisation (ESO) on 30 June 2021.