1. In 1961, the Seattle World's Fair opened on May 5th. Known as Century 21 Exposition, it attracted almost 10 million visitors and showcased futuristic inventions such as the Space Needle.

2. May 5th, 1983, marked the completion of the first phase of the Washington State Convention Center in Seattle. The Center features the largest ballroom in the Pacific Northwest and has since expanded to include additional meeting spaces.

3. In 1991, the Mayflower Park Hotel in Seattle celebrated its 70th anniversary on May 5th. The hotel, which first opened in 1927, was built on the site of the coin-operated Bimbo Theatre and has hosted countless famous guests throughout the years.

4. On May 5th, 2017, the Washington State Department of Transportation opened the new State Route 520 Bridge over Lake Washington. The new bridge features expanded bike and pedestrian paths and a state-of-the-art intelligent transportation system.

5. May 5th, 2020, marked the 54th anniversary of the signing of the Seattle Open Housing Ordinance. The ordinance, passed in 1964, outlawed housing discrimination based on race, religion, or national origin and was a significant step towards ending segregation in Seattle.