Before air travel, cruise ships were the only option for getting from one side of the ocean to the other. Although trans-Atlantic cruises may no longer be necessary, they're still available for those wanting to experience a bit of the way things used to be while crossing in first class. Most of these cruises are seven to eight nights between New York or Boston and Southampton, England, usually with a port of call on either side and a full five or six sea days in a row. Cunard Line’s Queen Mary 2 is the only ship that offers regular crossings year-round, while other ships do a handful of Atlantic crossings a year, sometimes as part of repositioning cruises.