Modern Marvels

High Voltage (10x29)

Air date: Jun 24, 2003

Look closely at those tall metal towers that span the country and you might see tiny specks climbing up the soaring steel like spiders on an enormous web. Meet the courageous linemen who erect, string, and repair 250-foot high electrical transmission towers, working with energized power lines that can carry up to 765,000 volts!