Old forums indicated there was or is a Cruise that goes from Hainan to Halong Bay and that people (at least Chinese locals) do not need a visa.

I am not sure if this is because it is a pre-set tour or because there is a time limit on the stay. Where can reservations or bookings be made? I would like to find out what rules might apply for an American staying in Hainan.

Are there any other cruises from Hainan? Any websites or places to make reservations?