Mysteries at the Monument: Ellis Island, Sailing Stones, Alamo Treasure

NewYork's Ellis Island is filled with the history of the millions of immigrants who passed through its historic buildings. But one famous family, immortalized in a classic film, almost never made it through at all. Deep inside California's Death Valley National Park lies a dried-out lakebed containing a set of mysterious stones which seemingly have the ability to sail across the sand, baffling scientists to this day. And in San Antonio, Texas is a legendary and hallowed fortress which once saw one of America's most famous battles. Some believe that a vast treasure may be buried somewhere within its stone walls.