In mountainous northeast India, the sinewy bridges that span the region’s rivers and streams are natural—and man-made—wonders. They’re fashioned from the pliable, strong roots of Ficus elastica, a unique species of Indian rubber tree. The tree’s roots can be coaxed into growing across the water, and are manipulated into overpasses by the War Khasi and War Jaintia people of Meghalaya state.

Some of the bridges are over 500 years old, and stretch up to 150 feet long. However, nobody knows who first made the bridges, where they come from, or how many there are. Meanwhile, the root bridges are buried deep in the jungle—meaning that many people have never seen or heard of them.

Patrick Rogers of the Living Root Bridge Project wants to change this. He’s launched a crowdfunding campaign to fund an endeavor to locate, measure, and document the region’s root bridges, ladders, and observation platforms. He plans to log his findings into a blog or database, which he hopes will encourage awareness and preservation of the unique structures. That way, locals can benefit from the tourism they bring while also maintaining a centuries-old tradition amid threats of modernization.

Rogers plans to take multiple trips to northern India over the next few years, and will use the donations to cover on-the-ground expenses.To learn more about his quest to keep India's root bridges alive and growing, visit the Living Root Bridge Project's homepage or check out his blog.

[h/t Inhabit]