- Quality: HD
- Audio / Subtitle: LEGENDAS-PT
- Date: 2011
North America�s Great Lakes are the largest system of free fresh water on earth, wielding huge influence on the continent. Over 34 million people live by their shores in some of greatest cities in the world. This groundbreaking television program pulls a virtual plug on the huge lakes, using computer-generated imagery to reveal hidden secrets of their human history and changing geological past.