Roman Catholic church and minor basilica within the Sanctuary of Our Lady of Lourdes. Its main theme is a celebration and depiction of the Rosary. The Rosary Basilica, known as the "Lower Church", is the third of the churches to be completed on the site (after the Crypt and the Upper Basilica). It was designed by architect Leopold Hardy and completed in 1899. It was consecrated in 1901 and has a capacity of 1,500 worshippers. Its style is Neo-Byzantine. The nave is open and circular, surmounted by a dome. The dome contains sixteen circular stained glass windows. The fifteen spaces between these windows signify the fifteen decades of the traditional rosary. The nave is surrounded by fifteen smaller side chapels, one for each of the traditional Mysteries of the Rosary.