"Takes a comprehensive look at Operation Iraqi Freedom, from the military buildup and the shock and awe campaign to the fire-fight in Basra and the toppling of Saddam Hussein's statue. With spectacular footage never before seen in the U.S. and emotional first-hand accounts of soldiers, reporters and National Geographic's award-winning production team, 21 Days to Baghdad will provide an exclusive, insider's look at war strategy and the pivotal moments...

The largest masonry dome on earth, Florence's cathedral of Santa Maria del Fiore, is a masterpiece of ingenuity and a source of mystery. Historians and engineers have long debated how its architect kept the dome perfectly aligned and symmetrical as the sides rose and converged toward the center. To test the latest theories, a team of U.S. bricklayers will help build an experimental, mini-Duomo, using period tools and techniques.

He's been dead for more than 5,000 years and poked, prodded, and probed by scientists for the last 20. Yet Otzi the Iceman, the famous mummified corpse pulled from a glacier in the Italian Alps, continues to keep many secrets. Now, through an autopsy like none other, scientists will attempt to unravel mysteries about the ancient mummy, revealing not only the details of Otzi's death but also an entire way of life.

Scientists have struggled for centuries to pinpoint the qualities that distinguish humans from the millions of other animal species with which we share the vast majority of our DNA. Now, we explore those traits once thought to be uniquely human to discover their evolutionary roots.