The century 21 Exposition, also known as the Seattle World’s Fair, was held between April 21 and October 21, 1926 and drew almost 10 million visitors. Though the fair was primarily administered by the non-profit private Century 21 Exposition, Inc., the government of Seattle was deeply involved in development and execution. The Mayor’s Office spearheaded a Downtown Beautification program, the Board of Public Works conducted oversight and licensing for building projects on municipal land, and the engineering Department improved the downtown transportation network and improved the water/sewer utility and provided underground lighting. Seattle City Light provided a key role in developing the Pavilion of Electric Power, an exhibit featuring a 40-foot tall depiction of a hydroelectric dam.
Further resources at the Seattle Municipal Archives:
