The Bahá'í House of Worship in Wilmette, Illinois, is the oldest surviving Bahá'í House of Worship in the world, and the only one in the United States.
By 1922, the first part of the building, the Foundation Hall, was mostly finished, and Bahá'ís began using it as a meeting place. Progress on construction soon stalled, however, as funds began to dwindle, and residents of Wilmette began expressing displeasure with the construction site. At this point, many strange rumors about the structure began to circulate. Some people believed that the building was used by the Bahá'ís to keep a live white whale. Others said that the building was a refueling station for captured German submarines that had been brought to the Great Lakes.
Construction resumed as contributions from Bahá'ís began to increase, and in 1930, the George A. Fuller Company was hired to complete the building's superstructure. The superstructure was completed in 1931, and a year later, John Joseph Earley was hired to begin work on the building's concrete cladding. A model of the temple was placed on display at Chicago's 1933–34 Century of Progress Exposition, and people began travelling to Wilmette to see the building taking shape. The exterior of the building was completed in January 1943.
Work remained to be done on the interior cladding of the structure, as well as the landscaping around the building. Louis Bourgeois' designs for the interior were incomplete. He had died in 1930, before he could finish his plans, so in 1947, Alfred Shaw was hired to work on the interior detailing of the building. A plan for the building's gardens was approved in 1951, based on a design by Hilbert E. Dahl.