THE NETHERLANDS: Most ancient Romans probably couldn’t swim, so they put their lives at risk whenever they needed to cross a river. Sometimes, they would entreat protective gods to provide them safe passage. A collection of more than 100 coins dating from the 1st century B.C. to the 1st century A.D. found near the town of Berlicum likely marks the spot where Roman travelers once forded the River Aa and tossed coins into the water as offerings, hoping to reach the opposite shore unharmed.