Basilica of the National Shrine of the Immaculate Conception - largest Catholic church in the U.S.

The Basilica of the National Shrine of the Immaculate Conception on Michigan Avenue NE is the largest Roman Catholic church in North America and one of the largest in the world by interior area. Built primarily in the 20th century and dedicated as a national shrine, the basilica contains numerous chapels, extensive mosaics, and a grand domed interior reflecting a variety of devotional traditions. It serves both as a place of worship and as a national Catholic shrine, hosting liturgies, pilgrimages, and cultural programs. Its scale and national role make it a singular religious landmark in Washington, D.C.