The Green Unknown: Travels in the Khasi Hills is Patrick Rogers’ first-person account of traveling by foot in northeast India in order to document the presence and locations of a rare architectural eco-wonder known as a “living root bridge.” These are found only in northeast India. No comprehensive listing of them exists. It had been thought that they were few in number. But on previous travels in India, Rogers had heard rumors of the existence of far more root bridges than the few that had been identified and catalogued. And so he headed into the Khasi Hills alone to find them. On his first trek, besides his backpack he had only a hand-drawn map from a native to the area. On subsequent treks, he ventured further in without a map, relying on his experience and information he could obtain from Khasis that he met along the way.

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