PATTANAM, India -- Pottery shards, beads, Roman copper coins, and ancient wine bottles litter the strata beneath this small seaside village in India's southern Kerala state. The 250 families, mostly agricultural laborers, who live in Pattanam, 260 kilometers (161 miles) north of Kerala's capital Thiruvananthapuram, find the objects pretty, but would rather dig up the ground and build larger homes. But according to archaeologists K.P. Shajan and V. Selvakumar, they may be destroying the remnants of Muziris, a well-documented trading port where Rome and India met almost 3,000 years ago. They say that, based on remote sensing data, a river...