On this day in 1937 the Golden Gate Bridge was opened. This engineering marvel is an icon of not only San Francisco, but of America. It's a symbol of America's drive to achieve during the great depression. On a side note, it now attracts people from all around the world who want to kill themselves by jumping off of it. Not something its designers wanted to be associated with it.
On this day in 1941 the British navy sunk the Bismarck. After sinking the British battleship HMS Hood, it became a priority to sink the pride of the German navy. The Bismarck had been damaged in the battle and was trying to make it to a port in occupied France. But a seaplane spotted it and hit its rudder with a one in a million shot with a torpedo. Unable to navigate, the Bismarck was now a sitting duck and was finished off by a number of the British navy.
On this day in 1692 the Salem witch trials began. One of the darker hours of early American history, these trials represented the fear of the unknown and the power of accusation.