Chincha, in southern Peru, is one of several river valleys along the desert coast fed by Andean highland waters, which have long been key to irrigation agriculture. About 25 kilometers out to sea are ...

The heaps of khipus emerged from garbage bags in the back of the tiny, one-room museum—clumps of tangled ropes the size of beach balls. Sabine Hyland smiled as she gazed down at them and said, “Qué ...