Guanyin, a bodhisattva sometimes called the “Goddess of Mercy,” is revered by Chinese practitioners of Buddhism, Daoism, and folk religion alike as a savior of fishermen and sailors. Appropriate, then, that a small island off the coast of Taiwan would have a pilgrimage site dedicated to her. In a sacred cave hidden in the hills of Green Island, the slow process of erosion by dripping water has, over the course of tens of thousands of years, created a stalagmite said by some to resemble the bodhisattva. A minor pilgrimage industry…