Thrill Waterpark at Perfect Day at CocoCay.
Brittany Chang/Insider
- Cruise lines don't just own big boats — they also own private islands in places like the Bahamas and Belize.
- The properties have proven valuable for cruise lines like Carnival, its CEO said in March.
- See photos of the 6 private islands owned by Royal Caribbean, Carnival, MSC, and Disney.
1. Castaway Cay, Disney Cruise Line
David Roark/Disney Cruise Line
Disney Cruise Line signed...