San Juan is Puerto Rico’s capital and largest city, sits on the island’s Atlantic coast. Its widest beach fronts the Isla Verde resort strip, known for its bars, nightclubs, and casinos. Cobblestoned Old San Juan features colorful Spanish colonial buildings and 16th-century landmarks including El Morro and La Fortaleza, massive fortresses with sweeping ocean views, as well as the Paseo de la Princesa bayside promenade Culebra Island is a small, sparsely populated island and a surrounding group of cays off the east coast of Puerto Rico. In the northwest, Flamenco Beach is a long crescent of white sand and turquoise water backed by tree-covered hills. Nearby Tamarindo Beach offers clear waters full of fish, sea turtles, and rays. In the southwest, Punta Melones beach is known as a viewpoint for dramatic sunsets. Vieques Islandis a Caribbean island off Puerto Rico’s eastern coast. It’s known for boat tours of Bioluminescent Bay (or Mosquito Bay), where microorganisms give the water a blue-green glow. It also offers secluded beaches and snorkeling. Wild horses roam the countryside, much of which is preserved as the Vieques National Wildlife Refuge. The Fuerte de Vieques is a mid-19th-century Spanish fort and museum.