The Grotto depicts Our Lady appearing to St Bernadette at Lourdes. Devotion to Mary increased in the early part of the 20th century. The SHC grotto was built in 1913 from the boulders and rocks found around the property, and collected by the boarders.
In May just before the school holidays all the students processed to the grotto, each with a small bouquet of flowers for Mary and placed flowers on and around the grotto. As the procession continued, they would sing hymns accompanied by the organ being played inside and recite the rosary. The Head Prefect was given the honour of placing a crown of flowers on Mary's head. This was called the 'Crowning of Our Lady with Flowers'. The grotto would be floodlit and there was a trickle of water flowing into the fountain, it is now covered with ivy and roses.
There is a plaque on the front of the grotto reads "This statue and grotto were blessed by his Grace, the Most Rev. Carr on the 11th of February 1914".