Source: HistoryNet.com
1534: Jacques Cartier sets sail on a voyage to Canada in two ships, with 61 men.
1770: Captain Cook discovers Australia.
1775: British troops begin the siege of Boston.
1809: Napoleon Bonaparte defeats Austria at Battle of Abensberg, Bavaria.
1841: Edgar Allen Poe's first detective story is published.
1879: The first mobile home (horse-drawn) is used in a journey from London to Cyprus.
1914: James Duffy of Canada wins the 18th Boston Marathon in 2:25:01.2.
1931: Opening of new Welland Canal, linking Lake Erie and Lake Ontario; wide enough to carry big lakers.
1940: The first electron microscope is demonstrated.
1967: U.S. planes bomb Haiphong for first time during the Vietnam War.
1999: Two students enter Columbine High School in Littleton, Colorado and open fire with multiple firearms, killing 13 students and teachers, wounding 25 and eventually shooting themselves.