Portal:United States/Anniversaries/June/June 20
- 1782 – Congress adopts the Great Seal of the United States (original seal die pictured).
- 1819 – The U.S. vessel SS Savannah arrives at Liverpool, United Kingdom. She is the first steam-propelled vessel to cross the Atlantic, although most of the journey is made under sail.
- 1840 – Samuel Morse receives the patent for the telegraph.
- 1863 – West Virginia is admitted as the 35th U.S. state.
- 1963 – The so-called "red telephone" is established between the Soviet Union and the United States following the Cuban Missile Crisis.
- 2003 – The WikiMedia Foundation is founded in St. Petersburg, Florida.