Unexplained Historical Events

When a German Zeppelin burst into flames over Lakehurst, New Jersey, speculation began almost immediately that it was sabotage, but was it? How is it possible for 5,000 men to simply disappear in a country the size of South Carolina with their only trace being a stone inscription dated 108 AD? Why would a captain and his crew abandon a perfectly sound ship that contained 6 months of food and supplies? These are some of the unexplained historical events that baffle historians to this day...