India, Aug. 3 -- What does it take to unearth a hero stone? Amid growing efforts to document these tiny memorials, particularly across Tamil Nadu, archaeologists, scholars and volunteers are undertaking what are essentially modern-day treasure hunts. They wade through dense forests, trek across arid wastelands and wander through urban construction debris, looking for signs of a memorial to a fallen hero. Each memorial is tangible proof of a different time, a different tongue, a different people and a different way of life, says Sudhakar Nalliyappan, a heritage conservationist and founder of the NGO Yaakkai Heritage Trust. Nalliyappan leads a collective of 50 people, including archaeologists, historians and volunteers, who are currently on a...