The Alaskan Highway stands today as one of the boldest homeland security initiatives ever undertaken.
The international race to develop biological weapons during the 20th century.
It was the largest fire in American history: by the time it was all over, more than three million acres had burned and at least 78 firefighters were dead.
The Pennsylvania Railroad Company accomplished an enormous engineering feat, but destroyed a great architectural monument.
Engineered by William Barclay Parsons, the 21-mile, four-track route of the New York City Subway was the largest public works project in history.
The worldwide migration by eager gold-seekers turned California into a land of opportunity and fierce competition.
The story behind the development of the oral contraceptive that put women in control of birth control.
After 18 years of struggles, the Golden Gate Bridge opened on May 27, 1937.