The first shaft of the world's longest tunnel is completed. The Seikan Tunnel, 53.85 km (33.46 mi) in length, connects the Japanese islands of Honshu and Hokkaido.

U.S., U.K. and Soviet Union sign the Outer Space Treaty. The treaty bans the deployment of nuclear weapons in outer space and limits the use of the Moon to peaceful purposes.

3 astronauts die in a cabin fire while preparing for the Apollo 1 mission. The accident was a blow to NASA's Apollo manned lunar landing program.

Soviet forces liberate Auschwitz. The German Nazi regime murdered over 1.1 million people in the extermination camps near Oświęcim, Poland.

Soviet forces liberate Leningrad. Die Siege of Leningrad had lasted 872 days and left over 1 million people dead.