Over at Archive.org, you can find a large number of episodes of the old time radio series You Are There to stream or download. This unique series combined major historical events with then-modern journalistic techniques, as each week it imagined how a CBS News radio crew would document important moments in world history.
Some episodes of interest that are available on the site:
“The Last Days of Pompeii” (originally aired August 25, 1947, and rebroadcast on April 11, 1948)
“The Assassination Of Julius Caesar” (originally aired February 15, 1948, and rebroadcast on April 24, 1949)
“The Death of Socrates” (originally aired March 14, 1948)
“The Fall of Troy” (originally aired April 25, 1948, and rebroadcast on October 24, 1948)
“The Conspiracy of Catiline” (originally aired April 12, 1948)
“The Rise of Alexander the Great: Peace Offer” (originally aired March 6, 1949)
“The Rise of Alexander the Great: Battle for Asia” (originally aired March 13, 1949)
“The Rise of Alexander the Great: Mutiny in India” (originally aired March 20, 1949)
“Thermopylae” (originally aired April 16, 1950)
Grumio: Life in the Middle 