- 1374 BC Solar eclipse lasting 2 minutes 7 seconds is seen at Ugarit by Mesopotamian astronomers, "On the day of the new moon, in the month of Hiyar, the Sun was put to shame, and went down in the daytime, with Mars in attendance."
- 1654 Bridge at Rowley, Massachusetts, begins charging tolls for animals
1808 Day depicted by Spanish painter Francisco Goya in his "The Third of May," which he paints in 1814
Byron Swims the Hellespont
1810 English poet Lord Byron swims across the dangerous Hellespont Strait in Turkey (modern day Dardanelles)
- 1830 First regular steam train passenger service in the US starts in South Carolina, with U.S.-built locomotive “The Best Friend of Charleston”
- 1923 First non-stop North American transcontinental flight from New York to San Diego is completed
- 1952 First airplane lands at the geographic North Pole
- 1956 A new range of mountains is discovered in Antarctica, with two peaks over 13,000 feet
- 1965 First use of satellite TV, Today Show on Early Bird satellite
- 1978 "Sun Day": solar energy events held in the US
- 1978 First unsolicited bulk commercial email ("spam") is sent by a Digital Equipment Corporation marketing representative to every ARPANET address on the US West Coast
- 1985 Date of $5 million check in "A View To A Kill"
- 2000 Sport of geocaching begins with the first cache placed and the GPS coordinates posted on Usenet
- 2013 Aorun zhaoi, a Theropod dinosaur dating from 161 million years ago, is discovered in China
Largest Concert for a Female artist
2025 Lady Gaga's free concert at Copacabana Beach in Rio de Janeiro, Brazil, draws crowd estimated at 2.5 million attendees, the largest concert in history for a female artist; police later reveal they thwarted a bombing attempt
