A quiet walk in the woods can be a spiritual experience, and countless hikers head to redwood groves and high places to find a sense of awe. But if following a dirt track is a kind of prayer—the hypnotizing rhythm of feet and breath an ancient song—some trails are true religious pilgrimages, routes laid down by the faithful.From the high peaks of South Korea to an Irish landscape of heather and bogs, these hikes draw believers from around the world, following paths trod by Christian pilgrims, Buddhist monks, and Celtic pagans. And whether they sleep in historic abbeys or under the stars, devotees hike in a long tradition of spiritual seekers in the wilderness. With wild beauty and fascinating culture, these trails call even secular trekkers to make the journey, pulling on their boots for the hike of a lifeti