2008 Summer Olympic Games, Olympics, Beijing, Facts, News, Photos -- National Geographic

This presentation requires Flash. Please click here to download the free Flash player.

The heart in an average lifetime will have pumped about one million barrels of blood—enough to fill more than three supertankers.

Before he was known as Muhammad Ali, a young American boxer named Cassius Clay won gold in the light heavyweight event at the 1960 Summer Games in Rome.

With a population of 1.3 billion, China is a land of big numbers. More than five million people call Beijing home, and more than a hundred cities have a population of at least one million.

In 1924, Finland's Paavo Nurmi, nicknamed the "Flying Finn," stole the world's attention at the Summer Games in Paris. He ran away with three team and two individual gold medals in track and field.