The Balearics are synonymous with indulgence and the hordes of holidaymakers on package trips who flood Ibiza, Menorca, and Majorca each summer. But there's one small island in the cluster that has yet to be overrun: Formentera, 11 miles off the southeastern coast of Ibiza.

In the late 1960's, this bone-dry 33-square-mile island was tended by a few hardy farmers—until counterculture types, drawn by its windswept, old-world vibe, colonized it. Today, there are few cars and no stoplights, and the only personwho owns enough land to build an airport refuses to do so, for fear it will spoil the place. Nevertheless, the island is quickly evolving into a monied bohemian playland—think brunch of organic granola served with vintage champagne—and has recently become a popular destination for the likes of Kate Moss and Elle Macpherson when they want to escape the flashbulbs. Now is the time to book for next summer: with very few hotel rooms, affordable prices, and word spreading fast, by the New Year all the reservations are sure to be taken.

HOW TO GET THERE An hourly ferry (34-902/160-180; $20 round-trip) from Ibiza drops off bathing beauties in the rustic capital of Sant Francesc Xavier.

TOP BEACHES With snowy sands and crystal blue water that stays warm most of the year, Formentera's coastline is like a wide-open Caribbean shore dropped into the middle of the Mediterranean. Scope out the secluded cove of Cala Sahona on the island's west side, the placid (clothing-optional) Playa Illetas, and the snack shack-lined (also nude-friendly) Playa Mitjorn to the south.

WHERE TO STAY Everybody's buzzing about Leah Tilbury's four-room boutique B&B, Las Banderas (Playa Mitjorn; 34-609/577-417; doubles from $80; open mid-April through October 15), decorated with oversized antique furniture, fluttering curtains, and towers of sunbaked art books. When Las Banderas is full, head to the basic Hostal Bellavista (34-971/322-255; doubles from $73), close to the port of La Savina, where cafés and market stalls are clustered along the water.

WHERE TO EAT The chef at Juan y Andrea (Playa Illetas; 34-630/930-913;; lunch for two $80) steams freshly caught lobster, which is then delivered to patrons at ramshackle tables on the beach. Es Moli de Sal (Playa Illetas; 34-971/187-491; lunch for two $80) serves fideua (a version of paella made with noodles) high above the sea in a converted windmill.

NIGHTLIFE After hours, hit the dance floor at Blue Bar (Playa Mitjorn; 34-971/187-011), the local answer to Ibiza's Café del Mar, or the waterfront 10.7 (Playa Mitjorn; 34-971/328-485).

BEST-KEPT SECRET Espalmador is a tiny, uninhabited island off Formentera's northern shore. A wade through the shallow waters at low tide is rewarded by a soak in two natural mud baths—free to anyone willing to break away from the sparkling sand.
—Mark Ellwood

Juan y Andrea

Es Moli de Sal

Hostal Bellavista

Las Banderas, Sant Francesc Xavier