Cardinal Donald W. Wuerl will be the principal celebrant of a Mass on Friday, Dec. 8, at noon to dedicate the newly completed Trinity Dome Mosaic at the Basilica of the National Shrine of the Immaculate Conception.

The dedication of the Trinity Dome Mosaic will take place on the Solemnity of the Immaculate Conception of the Most Blessed Virgin Mary, the patronal feast day of the United States and the National Shrine.

As Archbishop of Washington, Cardinal Wuerl also serves as chairman of the National Shrine’s Board of Directors. With the dedication of the Trinity Dome Mosaic, the National Shrine will be completed according to its original architectural and iconographic plans of nearly a century ago.

When he visited the National Shrine on Sept. 23, 2015, Pope Francis blessed the first

segment of mosaic fabricated for the Trinity Dome containing the beginning and the

end of the Nicene Creed: “I believe in one God” and “Amen.” Cardinal Kevin Farrell – the former bishop of Dallas and a former auxiliary bishop of the Archdiocese of Washington who now serves at the Vatican as prefect of the Dicastery for the Laity, Family and Life – will represent Pope Francis at the Mass and dedication.

The Trinity Dome Mosaic is one of the largest mosaic installations of its kind in the

world, covering more than 18,300 feet of the interior surface of the central dome of the National Shrine. Composed of more than 14 million pieces of Venetian glass in

more than 1,000 color variations, the mosaic depicts the Most Holy Trinity, the Blessed Virgin Mary as the Immaculate Conception, and a procession of saints and angels, the four evangelists, and the Nicene Creed.

This past Mother’s Day, Catholics from across the United States contributed to a special collection to raise funds for the completion of the Trinity Dome.

The Dec. 8 Mass and dedication will take place at noon in the National Shrine’s Great Upper Church and will be open to the public. A reception follows the Mass. The National Shrine, located at Fourth Street and Michigan Avenue, N.E., has ample free parking and is convenient to the Metro’s Brookland/CUA station on the Red Line.