In this March 31, 2011 photo, a centuries-old tablet that warns of danger of tsunamis stands in the hamlet of Aneyoshi, Iwate Prefecture, northern Japan. Hundreds of such markers dot the coastline, some more than 600 years old. Collectively they form a crude warning system for Japan, whose long coasts along major fault lines have made it a repeated target of earthquakes and tsunamis over the centuries. AP Photo / Vincent Yu