Building The Ultimate Defences | How Did They Build That? | Spark

An investigation into the greatest man-made structures of all time, exploring how new materials and construction techniques have allowed engineers, builders, and architects to work to the limits of their ability. The series focuses on the buildings that re-wrote the rulebook and the architects, engineers, and builders who made the impossible possible. First Aired: November 26, 2000. Content Provided By TVF International. Any Queries Please Contact hello@ Subscribe to Spark for more amazing science, tech and engineering videos -