April 25th

The largest tornado outbreak ever recorded hits the U.S. 348 people in six states were killed during the outbreak, which encompassed a total of 358 confirmed tornadoes.
2011 Super Outbreak
The Dow Jones industrial average topped 13,000 for the first time, ending the day at 13,089.89.
The Georgia legislature voted to scrap the "Confederate flag" design from its state flag.
Modern display of the Confederate flag
Islamic forces took control of most of the Afghan capital Kabul following the collapse of the Communist government.
Afghan Civil War (1989–92)
Violeta Barrios de Chamorro was inaugurated as president of Nicaragua, ending 11 years of leftist Sandinista rule.
Violeta Chamorro
The German news magazine, Stern, announces discovery of Hitler's diaries. The documents were later exposed as forgeries, triggering one of the most spectacular media scandals in history. Experts believe that Hitler never kept a diary.
Hitler Diaries
In Portugal, the fascist Estado Novo is overthrown in a bloodless coup. The leftist Carnation Revolution was lead by military officers and supported by widespread civil resistance.
Carnation Revolution
Polaroid Corp. introduced its SX-70 folding camera, which ejected self-developing photographs.
Polaroid SX-70
The St. Lawrence Seaway opened to shipping.
Saint Lawrence Seaway
Bell labs announces the 1st solar battery made from silicon. It has about 6% efficiency.
The double helix structure of DNA described for the first time. Francis Crick and James D. Watson published their groundbreaking findings about the molecule containing genetic information was in Nature that day.
Molecular Structure of Nucleic Acids: A Structure for Deoxyribose ...
U.S. and Soviet forces linked up on the Elbe River, in central Europe, a meeting that dramatized the collapse of Nazi Germany.
Battle of Berlin
The first seeing eye dog was presented to Morris S. Frank.
Morris Frank
Allied soldiers invaded the Gallipoli Peninsula in an unsuccessful attempt to take the Ottoman Turkish Empire out of World War I.
Gallipoli Campaign
New York became the first state to require automobile license plates.
Vehicle registration plates of New York
The United States declared war on Spain.
United States declaration of war upon Spain
Radio pioneer Guglielmo Marconi was born in Bologna, Italy.
Guglielmo Marconi
Construction of the Suez Canal begins. The waterway connecting the Mediterranean Sea and the Red Sea became the shortest sea link between Europe and Asia.
Suez Canal
Thornton Affair: Open conflict begins over the disputed border of Texas, triggering the Mexican-American War.
Mexican–American War
Highwayman Nicolas Jacques Pelletier became the first person under French law to be executed by guillotine.
English Convention Parliament meets and votes to restore Charles II.
Convention Parliament (England)