Flight
There are no direct flights from the US to Sanya, common connections go through Hong Kong or Macau since they are near Hainan Island, but you are of course free to book other options.
Travel Note
For US citizens travel to Hainan is Visa free for 30 days. You must have a return flight booked before you arrive. Travel to Hong Kong is Visa free for 90 days and for Macau it is Visa free for 30 days. Your passports must be valid for at least another 6 months before you go.
Hotel
This will be the location for wedding events, but you may stay at nearby hotels if you wish. Travel between hotels will be your responsibility. The Sheraton and the Ritz Carlton neighbor the Hilton.
Hotel
Hotel