San Juan, Puerto Rico's capital, blends old and new. Founded in 1521, it was a key Spanish colonial port; El Morro still guards the harbor. Old San Juan, behind thick stone walls, keeps blue cobblestone streets, plazas, and colorful heritage buildings, and serves as the island's cultural hub. Nearby Santurce is the trendiest district, with shops, restaurants, and nightlife. Minutes away, Condado and Isla Verde offer iconic palm-lined Atlantic beaches.

St. John, the smallest of the three main U.S. Virgin Islands, is a pioneer in Caribbean eco-tourism. Over half its 20 square miles are undeveloped, protected as Virgin Islands National Park, created in 1956 from land donated by Laurance Rockefeller. Its beaches, coast, and seas are also protected. Days center on hiking, swimming, snorkeling, and sailing. Cruz Bay is the commercial hub and ferry landing from St. Thomas. A winding road leads to quiet Coral Bay and its sheltered harbor.

Once a sleepy fishing village, Marigot became St. Martin's capital under Louis XVI, who built Fort Louis to guard the harbor. Its ruins overlook Marigot Bay and are worth the short hike. The town charms with winding streets, colorful buildings, duty-free boutiques, and Marigot Market for local food, spices, art, and crafts. Try mauby and enjoy French, Creole, and international dining. Nearby Grand Case is famous for top eateries, and Marigot is a great base for exploring St. Martin's 37 beaches.

Les Saintes is a volcanic archipelago of two islands and seven uninhabited islets, ringed by coral reefs and clear seas. Terre-de-Haut, just over two square miles, is the most developed, with scenic bays, natural harbors, quiet beaches, and picturesque villages. Its laid-back days center on beachgoing, hiking, snorkeling, and diving. Bourg des Saintes has cafés, the church of Notre-Dame de l'Assomption, and Fort Napoleon, now a museum and botanical garden with sweeping views.

Canouan is a secluded Grenadine retreat with soft white-sand beaches, coves, turquoise seas, and offshore reefs for snorkeling and diving. Its name comes from an Arawak word for turtles; turtles nest on windward sands amid coral reefs, sea fans, and tropical fish. On the southern leeward coast, Charlestown is the main settlement, with a natural anchorage for sailboats and yachts. Mount Royal offers scenic hiking trails and tropical wildlife.

Curaçao has 30+ beaches and the cosmopolitan capital Willemstad, whose colorful historic center spans Sint Anna Bay and is linked by the floating Queen Emma Bridge. In Punda, find cafés, galleries, shops, and a floating market, plus Fort Amsterdam, a 17th-century synagogue, and the Curaçao Maritime Museum. Nearby Pietermaai is known for nightlife. Clear waters and reefs make snorkeling superb. On land, see prehistoric art in the Hato Caves and taste Curaçao's blue liqueur at Chobolobo.

Aruba pairs easygoing Caribbean charm with a sun-splashed, desert-tinged landscape and some of the region's clearest water. Just beyond the port, Oranjestad charms with pastel Dutch-colonial buildings, lively shops and cafes, while the island's famous beaches invite swimming, snorkeling and simple relaxation beneath the trade winds. Inland, rugged cacti, windswept shorelines and striking natural pools reveal a wilder side of this welcoming island.