On this day
– The 1906 Summer Olympics, not now recognized as part of the official Olympic Games, open in Athens.
– Tsinghua University, one of mainland China’s leading universities, is founded.
– Pravda, the “voice” of the Communist Party of the Soviet Union, begins publication in Saint Petersburg.
– The use of poison gas in World War I escalates when chlorine gas is released as a chemical weapon in the Second Battle of Ypres.
– The United Kingdom, Japan and the United States sign the London Naval Treaty regulating submarine warfare and limiting shipbuilding.
– The 1964-1965 New York World’s Fair opens for its first season.
– British yachtsman Sir Robin Knox-Johnston wins the Sunday Times Golden Globe Race and completes the first solo non-stop circumnavigation of the world.
– The first Earth Day is celebrated.
– Vietnam War: Increased American bombing in Vietnam prompts anti-war protests in Los Angeles, New York City, and San Francisco.
– The German magazine Der Stern claims that the “Hitler Diaries” had been found in wreckage in East Germany; the diaries are subsequently revealed to be forgeries.
– In an explosion in Guadalajara, Mexico, 206 people are killed, nearly 500 injured and 15,000 left homeless.
– Version 1.0 of the Mosaic web browser is released.
– Haouch Khemisti massacre in Algeria – 93 villagers killed.
– Disney’s Animal Kingdom opens at Walt Disney World near Orlando, Florida, United States.