The remarkable story of how a railroad was built connecting California to the East.
The international race to develop biological weapons during the 20th century.
The historic journey of Apollo 8 captivated the world in 1968 -- a bright spot in a year marked by political assassinations, race riots, and the Vietnam War.
Major Walter Reed's discovery in 1900 that mosquitoes spread yellow fever halted an outbreak and led to the disease's eventual eradication.
While the U.N. debated strategies for control of atomic energy, the U.S. Navy was preparing for nuclear tests on Bikini Island.
Brothers Wilbur and Orville Wright built a flying machine that made its first flight in Kitty Hawk, North Carolina in 1903.
George Eastman introduced the Kodak and Brownie camera systems and transformed photography into something anybody could do.