- 356 BC Herostratus sets fire to the Temple of Artemis in Ephesus, one of the Seven Wonders of the World.
- 365 Crete Earthquake followed by tsunami around the Eastern Mediterranean allegedly destroys Alexandria
- 1861 First Battle of Bull Run [Battle of First Manassas], 1st major battle of the US Civil War is fought near Manassas, Virginia, Confederate victory (US Civil War)
- 1904 After 13 years, the 4,607-mile Trans-Siberian railway is completed
- 1925 John T. Scopes found guilty of teaching evolution in the “Scopes monkey trial”, Dayton, Tennessee, fined $100 & costs
- 1969 Neil Armstrong becomes the first person to step on the Moon at 2:56:15 AM (GMT)
- 1970 Aswan High Dam opens in Egypt, enables human control of the flooding of the Nile
- 2015 On This Day changes its domain name and brand from HistoryOrb.com to OnThisDay.com
In the market square of Springfield, Missouri, Wild Bill Hickok shoots and kills Davis Tutt in what is regarded as the first true western showdown.
On July 21, 1865