The Trinity Dome is the central and largest dome of the National Shrine. This “Crowning Jewel” will be adorned in mosaic according to the original iconographic scheme of the Great Upper Church and will depict the Most Holy Trinity, the Blessed Virgin Mary as the Immaculate Conception, and a procession of saints who have an association with the United States and the National Shrine. The procession of saints includes, among others, St. Juan Diego (the first canonized male Native American), St. Kateri Tekakwitha (the first canonized female Native American), St. Teresa of Calcutta (an honorary American citizen), St. Francis Cabrini, M.S.C. (the first U.S. citizen to be canonized), St. John Paul II (the first pope to visit the National Shrine), and St. Junípero Serra (declared a saint by Pope Francis at the National Shrine in 2015 for the first canonization ever to take place on American soil). The Nicene Creed will encircle the base of the dome, while the dome’s four pendentives will feature the four Evangelists: Matthew, Mark, Luke and John.

During his visit to the Basilica of the National Shrine of the Immaculate Conception on September 23, 2015, Pope Francis blessed the preliminary segment of mosaic created for the Trinity Dome containing the words of the beginning and end of the Nicene Creed: “I believe in one God.” “Amen.”