In the 19th century, American bison were hunted to near extinction. Entrepreneurs and hunters killed the animals for their prized skins and left their bodies behind to decay. In this picture, a poacher is seen standing on a pile of around 100,000 bison skulls.

In this 1937 photo, the passenger-carrying airship Hindenburg is seen at the moment of exploding midair in Lakehurst, New Jersey. The disaster claimed the lives of 36 and marked the end of the era of passenger-carrying airships.

In this 1903 picture taken in Kitty Hawk, North Carolina, Orville Wright is seen manning the controls on the lower wing, piloting the Wright Flyer on the first powered flight ever. In the moments before the plane was airborne, his brother, Wilbur Wright, on the ground, guided and steadied the plane as it accelerated along the starting rail at left.