Trinity Dome Planning Underway

This year, we begin our five-year countdown to the centenary of the laying of the Foundation Stone of the National Shrine. During this time we hope to complete the National Shrine in its totality, specifically, the interior design of the National Shrine. The Trinity or Great Dome is the final movement in what the founder, Bishop Shahan, referred to as a great “Hymn in Stone.”

The general concept governing the iconographic scheme of the entire Shrine was outlined and established by the first Iconography Committee (1954-1958), chaired by Patrick Cardinal O’Boyle (1896-1987), Archbishop of Washington, John de Rosen (1891-1982) art consultant, and composed of scholars in ecclesiastical art, scripture, theology, and Mariology.

In 2006 and 2007, the north (Redemption) and south (Incarnation) nave domes were completed, respectively. Each dome contains 3,780 square feet of mosaic and rises to a height of 100 feet. The Great Trinity Dome, situated at the center of the cruciform Upper Church, is almost five times the size of one of these domes with 19,673 square feet, rising to a height of 129 feet.

The nave domes of the Great Upper Church.
Geraldine M. Rohling
The nave domes of the Great Upper Church.

A project of this magnitude requires several stages: planning, designing of the cartoon, manufacturing of the mosaic, installation of the scaffolding, preparation of the ceiling for the mosaic, installation of the mosaic, and the dismantling of the scaffolding. As with the nave domes, the most technically difficult and time-consuming element will be the installation of the scaffolding. This will entail building the equivalent of an additional 2-3 floors and rooms above the nave, which allow the work to proceed over an extended period without disrupting the liturgical celebrations. Similar to installation of the nave domes, only if the worshipper looks up, will he or she be aware of the scaffolding.

The theme of the dome is that of the Holy Trinity and the Blessed Virgin Mary and will also include a mosaic of the Immaculate Conception as well as the four Evangelists.

The Trinity Dome, five times the size of either the Redemption or Incarnation Dome, will also be five times as expensive. We have begun fund raising endeavors and welcome any assistance friends of Mary’s Shrine might be able to provide.

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