June 30

• June 30, 827
  The allied fleets of Muslims lands in southwestern Sicily beginning the Muslim conquest of Sicily
• June 30, 1097
  The Crusaders defeat the Turks at Battle of Dorylaeum
• June 30, 1520
  Moctezuma II is murdered by the Aztec as Spanish conquistadors under Cortez fled the Aztec capital of Tenochtitlan during the night and begin to plunder gold
• June 30, 1859
  French acrobat Charles Blondin crosses Niagara Falls on a tightrope as 5,000 spectators watch
• June 30, 1893
  Excelsior Diamond, the second largest rough diamond of gem quality ever found, is discovered at the Jagersfontein Mine in South Africa
• June 30, 1894
  Tower Bridge, a combined bascule and suspension bridge in London which crosses the River Thames, is opened
• June 30, 1908
  The Tunguska event near Tunguska River in central Siberia, Russia, later conjectured to be a meteorite strike, explodes 5-10 km above the forest and devastates thousands of square kilometers of Siberia
• June 30, 1923
  New Zealand claims Ross Dependency in Antarctica
• June 30, 1960
  Belgian Congo gains independence from Belgium as Republic of the Congo, triggering Congo Crisis, a conflict between nationalist faction under Prime Minister Patrice Lumumba and leader of country Mobutu Sese Seko
• June 30, 1963
  Cardinal Montini elected Pope Paul VI, 262nd head of Roman Catholic Church
• June 30, 1971
  Three cosmonauts die as Soyuz 11 depressurizes during reentry
• June 30, 1997
  Collapse of the currency of Thailand sparks the 1997 Asian Financial Crisis
• June 30, 2002
  Brazil national football team wins its fifth championship at the FIFA World Cup, held in South Korea and Japan