The <a href="https://en.wikipedia.org/wiki/Century_21_Exposition" id="mw2g" rel="mw:WikiLink" title="Century 21 Exposition">Seattle World's Fair</a> (Century 21 Exposition) opens. It is the first <a class="mw-redirect" href="https://en.wikipedia.org/wiki/World's_Fair" id="mw2w" rel="mw:WikiLink" title="World's Fair">World's Fair</a> in the United States since World War II.