On what day in 1914 was the Archduke Franz Ferdinand assassinated in Sarajevo?

As the key event that prompted the outbreak of World War I, the 'assassination in Sarajevo' took place on June 28, 1914, and was followed days and weeks later by various declarations of war that soon led to the world-wide conflict. Killed in the attack was the Austro-Hungarian Empire's Archduke Franz Ferdinand and his wife.