GOTHENBURG, SWEDEN—Joakim Wehlin of the University of Gothenburg and Gotland University has examined Bronze Age stone monuments that sit along Sweden’s Baltic Sea coasts. It had been thought that the monuments, which resemble stone ships, were used primarily as grave sites. Wehlin, however, thinks that they were used by maritime groups trading in metal objects. “It seems like the whole body was typically not buried in the ship, and some stone ships don’t even have graves in them. Instead, they sometimes show remains of other types of activities. So with the absence of the dead, the traces of the survivors tend to appear,” he explained. The monuments may have been used to mark ports, waterways leading inland, and potential meeting places.