Understanding

Caves (1x8)

Udgivelsesdato: Jan 15, 2001

Take a journey into the darkness, deep below the Earth's surface. Discover how caves were formed, learn who has walked their corridors through the ages, and see caves teeming with life that is amazingly different from our sunlit world above. Cities: Experts on subjects ranging from infrastructure to traffic flow explain what it takes to make a city run smoothly. Five cities are studied to see how they work and what gives them their personality.