Bridges are symbolic of all sorts of interpersonal and other connections. But they are also the physical connection between land masses, connecting different parts of a city, people and continents. Sometimes delicate in appearance, sometimes mighty, they are structures that have to meet the most stringent requirements. Great Inventions takes a journey through their history, from the simple plank over a stream to the suspension bridge that is over a kilometre long, and explains what aircraft have to do with bridges and how the tensile forces are kept under control.
