Explanation:

Khasi people  of Meghalaya have been trained to grow these bridges across the raised banks of streams to form a solid bridge, made from roots. The living bridges are made from the roots of the Ficus elastic tree, which produces a series of secondary roots that are perched atop huge boulders along the streams or the riverbanks to form bridges. , It takes ten to fifteen years to become fully functional, but they’re extraordinarily strong