A treehouse accommodation at Tonga's Mandala Island Resort. MUST CREDIT: Ben Newton, Mandala Island Resort. As I stepped off the little boat after 48 hours of travel, I felt a little like Tom Sawyer.

In the Kingdom of Tonga, respect for religion ranks as high as it does for royalty. The country shuts down on Sundays, when it's illegal to swim, play loud music or conduct business. At Mandala, we ...