Thanks to its UNESCO status, Baía de Sancho is protected from commercial development and mass tourism. Located in the Fernando de Noronha archipelago, off Brazil’s northeastern coast, the few visitors who do make it are thinned out even further by the precarious approach—a cliff-side descent down a series of ladders. The water thrives with marine life, from live coral to manta rays to dolphins.

This 50-mile stretch of shoreline from Huelva to Tarifa in Southern Spain sees 300-plus days of suns per year. The pinewood tree- and dune-lined beaches are free of crowds and high-rise developments. Its relative remoteness (the closest city, Seville, is three hours by car) and forceful coastal winds detract the masses, save for avid windsurfers who consider the area to be a sporting mecca.

Located on Tortola, the largest of BVI’s 60-plus islands, Long Bay is accessible by the steep, rugged road past Nail Bay or via anchored boat off the coast. This isolated inlet is ideal for swimming and snorkeling. Aside from the occasional sailboat—and the blue herons and pelicans who call Long Bay home—you’ll enjoy this stretch of paradise in near solitude.

Barbuda, some 25 miles to the northeast of Antigua, is a rarity in the Caribbean—miles of white- and pink-hued beaches largely remain untouched, with only a handful of full-service resorts to share them. Even the island's finest stretch, a 7-mile expanse from Palmetto Point to Coco Point, is typically so deserted that you can expect to share your day with seashells instead of people.

To reach Thailand’s Tonsai Beach, you have to take two longtail boats: one from Krabi or Ao Nang, and a second a from Railay Beach. The tiny stretch of white sand is surrounded by towering limestone cliffs, lush vegetation, and warm emerald water. Kick back, or go rock climbing, kayaking, or snorkeling—you’ll find an abundance of colorful coral reefs and cartoon-like fishes.

Thanks to the sheer cliffs that surround Shipwreck Beach, the milky-white crescent of sand on the Greek island of Zakynthos remains stunning and secluded. Accessible only by boat—cruises depart from the villages of Volimes or Porto Vromi—the famous shore gets its name from a marooned vessel, dating back to 1983, that remains half-emerged in the sand.

Trou d’Argent translates to “Money Hole,” a reference to the treasure that is rumored to be buried here; but we’d argue that the treasure may be the beach itself. Located on the eastern coast of Mauritius’s Rodrigues Island, the horseshoe-shaped, cliff-hugging cove touts striking views of the Indian Ocean. Access it from St. Francois, via 45-minute rocky cliff-top path shaded by filao trees.

Uoleva’s far-flung locale—within the South Pacific archipelago of Tonga’s Ha'apai Group—ensures that visitors who make the trek will be rewarded with pristine, nearly deserted beaches. Swim, fish, or snorkel among the western shores, which are peppered with vibrant coral reef. There are no more permanent island inhabitants than you count on your fingers, so distractions are few and far between.

Tucked away on Australia’s idyllic Whitsunday Island, this 4-mile beach owes its silky, talcum-powder sand to 99.8-percent pure silica grains. Backed by lush acacia forest and a shore that fades into crystal cerulean waters, the setting both recalls and transcends island clichés. Strict visitation limits enforced by the Great Barrier Reef Marine Park Authority ensure it stays that way.