The Grotto was initiated by Feliza Diaz in May 2016 in honour of her late husband Angel Diaz. Through the support of Parishioners of Santa Barbara and other local and foreign Benefactors, it was completed. It has a serene environment that can contain large numbers of groups and societies for their spiritual needs.

On August 15, 2022, Solemnity of the Assumption of Mary, hundreds of Parishioners celebrated the 1st Assumption Mass at the Grotto.