Ficus elastica
In the northeast Indian state of Meghalaya, Khasi and Jaintia tribal people have created living root bridges, which are a form of tree shaping. Here, simple suspension bridges are made by training the roots of the "Ficus elastica" species of banyan tree across watercourses. There are examples with a span of over 170 feet (52 m). They are naturally self-renewing and self-strengthening as the component roots grow thicker and some are thought to be more than 500 years old.