Coves scissor the island, with 39 beautiful beaches of varying length and hue. All are public though access is often via a rutted dirt road and/or through a fancy resort. Beaches on the western leeward half are generally hotter and calmer; those on the eastern windward side are, predictably, breezier with rougher swells (when not reef-protected). Warning: If it's too secluded, be careful. It's unwise to carry valuables; robberies have been reported on some remote strips. And never leave valuables in the car.

Wherever you stay, you're never far from the water. Beach samplers can sometimes use the changing facilities at bigger resorts for a small fee. Beach bars often rent chairs and umbrellas for roughly $6 and $3, respectively, but may waive the charge if you order lunch or drinks. Those who prefer topless sunbathing should head for the French side of the island, although the Dutch side is getting more liberal.

Dutch Side

Popular Cupecoy Beach is very close to the Dutch-French border at the island's southwest tip. It's a string of three sand beaches set against a backdrop of caves, rock formations, and dramatically eroded limestone cliffs. Locals come around with coolers of cold beer and soda for sale. The beach has two parking lots, one near Cupecoy and Sapphire beach clubs, the other a short distance to the west; parking costs $2. You must descend stone-carved steps to reach the sands. Cupecoy is also the island's major gay beach. Clothing is optional toward the northwest side of the beach. Warning: The steep drop-off and high swells make the beach hazardous for young children and weak swimmers; prevailing weather affects not only the surf, but the sand's width. Also: The Cupecoy area is seeing considerable new development, with disturbing reports of wastewater runoff onto the beaches.

The next strand down (west of the airport) is palm-shaded, white-sand Mullet Bay Beach, framed in seagrapes. Once it was the busiest beach on the island, but St. Maarten's largest resort, Mullet Bay, has been shuttered (save for a timeshare section) since Hurricane Luis in 1995, so it's never crowded, though locals flock here on weekends. Watersports equipment can be rented at a local kiosk, and two beach bars sell refreshments. The snorkeling is not bad along the rocks.

Near the airport, Maho Beach, at the Sonesta Maho Beach Hotel and Casino, is a classic Caribbean crescent, with vendors hawking colorful wares and locals inviting you to impromptu beach barbecues. This is one of the island's busiest beaches, buzzing with windsurfers -- and buzzed by jumbo jets that nearly decapitate the palm trees. When you spot a 747 coming into view, hang on to your hats, towels, and partner.

West of Philipsburg before you reach the airport, the 2km-long (1 1/4-mile) white sands of crescent-shaped Simpson Bay Beach ring the lagoon and are set against a backdrop of brightly hued fishing boats, yachts, and townhomes. This beach is ideal for a stroll or a swim (beware the steep drop-off), with calm waters and surprisingly few crowds.

Great Bay Beach is best if you're staying along Front Street in Philipsburg. This 2km-long (1 1/4-mile) beach is sandy and calm; despite bordering the busy capital, it's surprisingly clean and a splendid place to kick back after shopping, admiring the cruise ships from one of many strategic bars along the boardwalk. On a clear day, you'll have a view of Saba. Immediately to the west, at the foot of Fort Amsterdam, is picturesque Little Bay Beach, but it can be overrun with tourists disgorged by the cruise ships. You can actually climb up to the site of Fort Amsterdam itself. Built in 1631, it was the first Dutch military outpost in the Caribbean. The Spanish captured it 2 years later, making it their most important bastion east of Puerto Rico. Only a few of the fort's walls remain, but the view is panoramic.

On the east side of the island, Dawn Beach is noted for its underwater life and incredible sunrises, with some of the island's most beautiful reefs immediately offshore. Dawn has plenty of wave action, but it's suitable for swimming and snorkeling. Dawn Beach is now the site of the Westin Resort. This, in addition to the expansion of Oyster Bay Resort, has diminished its peaceful allure, but its remarkable reef, soft pearly sand, and views of St. Barts remain unchanged.

French Side

Baie Longue (Long Bay), on the west coast, is supremely conducive to R&R. Chic, expensive La Samanna hotel opens onto this beachfront, but it's otherwise blissfully undeveloped and uncrowded. Its reef-protected waters are ideal for snorkeling, but beware the strong undertow and steep drop-off. Baie Longue is to the north of Cupecoy Bay Beach, reached via the Lowlands Road. Don't leave valuables in your car, as break-ins have been reported along this stretch of highway.

Baie aux Prunes (Plum Bay) is a Cheshire grin of ivory sand, stretching luxuriantly around St. Martin's northwest point. This is a sublimely romantic sunset perch (bring your own champagne, as there are no facilities) that also offers good surfing and snorkeling near the rocks. Access it via the Lowlands Road past Baie Longue.

Baie Rouge (Red Beach) is caught between two craggy headlands where flocks of gulls and terns descend at dusk -- hence its western end is dubbed Falaise des Oiseaux (Birds' Bluff). The other side is marked by the Trou du Diable (Devil's Hole), a collapsed cave with two natural arches where the sea churns. You'll find superlative snorkeling here, but beware the powerful undertow. Beachwear becomes increasingly optional as you stroll west, though the modest will find several stands hawking sarongs, shorts, and sunbonnets. Baie Rouge is a charmer, from the serene waters to the views of Anguilla.

Baie Nettlé (Nettle Bay) unfurls like a carpet between the Caribbean and Simpson Bay, just west of Marigot. Access is right off the main highway running through Sandy Ground. The area has become increasingly developed, with several hotels, apartment complexes, watersports franchises (waterskiing and kiteboarding are quite popular), and tiny beach bars alternating with fancier restaurants. The view on the Caribbean side frames Anguilla, Marigot's harbor to the north, and the ruins of La Belle Creole along the Pointe du Bluff to the south.

Isolated Anse des Pères (Friar's Bay Beach) lies at the end of a winding, bumpy country road; its clearly signposted entrance intersects with the main highway between Grand Case and Marigot. This is a pretty, less-visited beach with ample parking. Shelling, snorkeling, and sunset-watching are all favored. Two beloved beach bars organize raucous themed bashes. Stop in at Kali's Beach Bar (tel. 590/49-06-81), a thatched bamboo hut splashed in Rasta colors, where Kali himself serves some of the island's best barbecue. Kali hosts "full-moon parties," featuring reggae bands on the beach along with a bonfire and plenty of drink. Tip: Have one of the staff here point you in the direction of relatively undiscovered Anse Heureuse (Happy Bay), a 10-minute walk north through underbrush over a hill from Friar's Bay (pause to drink in the views of Anguilla). It richly deserves the name, thanks to the tranquillity, fine snorkeling, and white-sand beach.

Grand Case Beach, a long, narrow ribbon right in the middle of Grand Case, is a small, pleasant beach that can get crowded on weekends but has none of Orient Beach's carnival-like atmosphere. The waters are very calm, so swimming is good -- although it's become a popular parking spot for visiting boats. A large section of the water has been roped off for kids to swim in safely. Unparalleled dining choices along the Caribbean's "Restaurant Row" run from lolos (essentially barbecue shacks) to gourmet bistros. For something in between, try Calmos Café, where you can watch the sun set over the beach with your feet in the sand and a drink in your hands.

To the east of Grand Case, follow the winding road up and over Pigeon Pea Hill. The spectacular setting of Anse Marcel comes into view. This lovely cove is home to two resorts, the Radisson St. Martin and Domaine de Lonvilliers. The adjacent Marina Port de Lonvilliers offers a handful of restaurants and shops, and the former le Méridien is now a Radisson, with additional recreational and gustatory opportunities. The beach itself is protected, with shallow waters ideal for families. You can swim here or else take a hike for 1 1/2 hours north over a hill and down to one of the island's most pristine beaches, Baie de Petites Cayes. This is the most idyllic spot on St. Martin for a picnic. A ribbon of brilliant white sand beckons, and the waters ripple from sapphire to turquoise. Part of the fun is the hike itself, with panoramic views stretching all the way to Anguilla.

On the east coast, Baie Orientale (Orient Beach) is where the action is. It's also a beauty of a beach. Eating, drinking, and people-watching qualify as sports, and many beach bistro/bars offer not only grilled crayfish Creole, but also live music, boutiques (with fashion shows), massages, parasailing, jet ski rentals, kiteboard instruction, and more. Of those beach bars marketing themselves as "The Five Stars of Orient Bay," Waïkiki Beach (tel. 590/87-43-19) is a favorite of the well-heeled barefoot St. Barts set, who down beluga caviar with Belvedere shots. Kontiki (tel. 590/87-43-27) has two sections: the main eatery and the Tiki Hut, serving a mix of dishes from jerk chicken to paninis, to quesadillas, to sushi. Bikini Beach (tel. 590/87-43-25), which also stays open for dinner, has a menu that runs from American-styled hamburgers to Spanish-influenced paella studded with lobster. Its southern end contains the naturist resort, Club Orient.

Baie de l'Embouchure, embracing Le Galion and Coconut Grove beaches, just south of Orient, is part of the St. Martin Réserve Sous-Marine Régionale, established to protect migrant waterfowl habitats and rebuild mangrove swamps. A coral reef encloses the bay: The calm, shallow water (you can wade up to 100m/328 ft. out) makes it ideal for small children -- it's the only beach on the French side where topless sunbathing is discouraged. Tiki carvings and blue umbrellas mark the appealing Le Galion Restaurant (also known as Chez Pat after owner Pat Turner; tel. 590/87-37-25). Up in the hills facing the bay is a handsome white house that was long the home of Romare Bearden, the celebrated American artist and collagist.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.