Eighteen hundred miles northeast of New Zealand, Niue can feel isolated. News on the island is only broadcast twice a week, swimming is frowned upon on Sundays, and, with just over 1,600 people on 100 square miles of the largest uplifted coral atoll in the world, it's the least populated self-governing nation on the planet after the Vatican. But the quirks are part of the allure of this rocky cave-ridden island. Visitors can angle for reef fish from traditional vaka sailing canoes ($55) or snorkel with humpbacks from July through September ($101).
But don't ignore the land. Chasms and caverns perforate the island by the thousands. Until the early 1800s, Niueans inhabited them instead of houses, and even today there are fewer than 100 accommodations on Niue. Go for the large studios at the recently opened oceanfront Matavai Motel, each of which has a private balcony perched on the rocky shore (from $106). The Huvalu Conservation Area tropical forest covers 13,000 acres, nearly one-quarter of the island, and has plenty of cycling opportunities. Mountain-bike the eight-and-a-half-mile Alofi-Liku and Vinivini Bush Roads rainforest circuit or ride the 42-mile road around the island past beaches and along limestone cliffs (bike rentals, $12 per day).
Access: Air New Zealand flies from Auckland weekly—the 3.5-hour flight crosses the International Date Line, arriving 20.5 hours before it departed.