Living root bridges
In most places around the world, bridges are constructed using concrete and steel. But in Meghalaya, bridges are grown !!! The original architects of this natural bridge building technology are the forefathers of the local tribes in Meghalaya. Though this ancient technology appears to be theoretically simple, practically it is very difficult and time consuming.
Roots of certain Ficus trees (including Ficus elastica, locally known as ‘Dieng jri ’) are trained to serve as pavements for these natural bridges across the rivers or steep valleys. Strong secondary roots of these trees are manipulated or trained to grow horizontally through the tunnels of hollowed betel nut trunks or bamboos. Over the years, the roots and branches of these fast growing trees get trained along the bamboo/betel nut guides until they meet and eventually supersede its support. At later stages, stones are inserted into the gaps to eventually gift us the beautiful walkways. Later still, the bridges are further improved upon with additional hand rails and steps.
While construction of modern concrete bridges may take 3-4 years, these living bridges take longer time to develop into a firm bridge, often around 15 to 25 years. However, the life of these bio-engineering wonders is estimated at 500 years, much more than the life span of most of manmade modern bridges. The bridges are made often for lengths of 50 to 100 feet and even up to 50-55 m length. They are proved to carry the load of up to 50 people at a time. Unlike the wooden bridges which may rot and decay in high rains, these root bridges remain alive and grow stronger over time. The development and upkeep of bridges is a community affair.