Culebra, Vieques and the Bio Bay

Off Puerto Rico's east coast lie the tranquil islands of Culebra and Vieques, the Spanish Virgin Islands, a slower, more idyllic world of stunning beaches and clear turquoise water. Culebra is home to Flamenco Beach, regularly ranked among the most beautiful beaches on earth, a glorious curve of powder-white sand. Vieques, larger and wilder, roamed by free-ranging horses, harbours Mosquito Bay, the brightest bioluminescent bay in the world, where microscopic organisms make the water glow an ethereal electric blue when disturbed on a dark night, a magical experience.

What you actually see

• Flamenco Beach - Culebra's world-famous white-sand beach.
• Mosquito Bay - Vieques's glowing bioluminescent bay by night.
• The snorkelling - the reefs and clear turquoise water.
• The wild horses - the free-roaming horses of Vieques.

When to go

December to April, the dry season, for the best weather and calmest seas; the bioluminescent bay glows brightest on dark, moonless nights, so time a bio-bay tour away from the full moon. The islands are reached by ferry or small plane and reward a relaxed overnight rather than a rushed day trip.

Honest expectations

The islands are quiet and low-key, with limited facilities and sometimes unreliable ferries, so they suit relaxed travellers rather than those seeking resorts or nightlife; some areas still bear scars from hurricanes and Vieques's former use as a military range. Swimming is not allowed in the fragile bio bay. For gorgeous, uncrowded beaches and the magical glow of the world's brightest bio bay, though, they are unforgettable.

Nearby

The main island's east coast at Fajardo is the ferry and flight gateway.