Living root bridges are a form of tree shaping common in the southern part of the Northeast Indian state of Meghalaya. They are handmade from the aerial roots of living banyan fig trees, such as Ficus elastica by the Khasi people and War Jaintia peoples of the mountainous terrain along the southern part of the Shillong Plateau. The pliable tree roots are made to grow through betel tree trunks which have been placed across rivers and streams until the figs' roots attach themselves to the other side. Sticks, stones, and other objects are used to stabilize the growing bridge This process can take up to 15 years to complete. The useful lifespan of any given living root bridge is variable, but it is thought that, under ideal conditions, they can in principle last for many hundreds of years. As long as the tree they are formed from remains healthy, they naturally self-renew and self-strengthen as their component roots grow thicker. At over 50 meters in length, the longest known example of a living root bridge is near the small Khasi town of Pynursla. It can be accessed from either of the villages of Mawkyrnot or Rangthylliang. There are several examples of double living root bridges, the most famous being the "Double Decker" root bridge of Nongriat Village.