Bamboo's tensile strength has been essential in the development of bridges. The Chinese invented suspension bridges using bamboo to cross rivers. Using only the exterior part of the bamboo, which is four times as strong as the interior, they created tension cables up to 120 meters long. Bamboo bridges were also constructed in India, and by the Incas in South America. In both cases, the structural cable was strung above the walking surface, which hung from it. And in Colombia, tension bridges were created using this amazingly strong material, with tensile strengths of up to 3,200 kg/cm2 for the species Guadua. Similar building techniques have also been used to create gabions to dam rivers and streams, where a long basket of bamboo is filled with stones with each end secured to the banks. Read More Here