The statue of Our Lady in the Grotto is located on the exact spot where Our Lady appeared to St. Bernadette. Below the statue of Our Lady is the spring which welled up from the spot dug by St. Bernadette on Our Lady's instructions. It was St. Bernadette who heard Our Lady identify herself as the Immaculate Conception, a heavenly confirmation from the subject herself of the proclamation of Pope Pius IX in Ineffabilis Deus four years earlier.
Here's some photos of the miraculously incorrupt body of St. Bernadette who died in April 16, 1869. I've always had a fascination with St. Bernadette ever since I read about her in the Incorruptibles.
All images courtesy of In Caritate non Ficta.