Columbretes Islands: A Pristine Marine Paradise Off the Costa del Azahar

Sitting roughly 30 nautical miles off the Castellón coastline, the Columbretes Islands are one of Spain's best-kept natural secrets. This tiny volcanic archipelago is a strictly protected marine reserve and a dream destination for divers, snorkellers, and wildlife enthusiasts. Better still, day-trip boats depart regularly from Las Fuentes Marina, just a 10-minute drive from Hotel Sancho III in Alcocéber.

Why the Columbretes Are So Special

The archipelago comprises four island groups — Illa Grossa (the largest and only one open to visitors), La Ferrera, La Foradada, and El Carallot. Formed by volcanic eruptions over a million years ago, the islands feature dramatic basalt cliffs, underwater caves, and seabeds plunging to 80 metres. Because fishing and anchoring are tightly controlled, marine life here is extraordinarily abundant.

• Seabird colonies — Audouin's gull, Eleonora's falcon, and Cory's shearwater nest here in significant numbers.
• Endemic species — The Columbretes lizard and several rare plant species are found nowhere else on Earth.
• Underwater biodiversity — Posidonia meadows, red coral, gorgonian fans, and large shoals of barracuda, grouper, and dentex thrive in the reserve.

World-Class Diving and Snorkelling

Divers consistently rank the Columbretes among the top five dive sites in Spain. Visibility regularly exceeds 30 metres, revealing vertical walls draped in red and orange coral, swim-throughs teeming with moray eels, and vast schools of amberjack. Even if you are not a certified diver, snorkelling around Illa Grossa offers unforgettable encounters with groupers the size of armchairs and octopuses in the shallows.

What to Expect on a Day Trip

Most excursions follow a similar format:

• Departure: Early morning from Las Fuentes Marina (around 8:00 AM).
• Crossing: Approximately 2 to 2.5 hours by fast boat.
• On the islands: Guided walk on Illa Grossa, visit to the historic lighthouse, snorkelling stops, and optional scuba dives.
• Return: Late afternoon, arriving back at the marina around 6:00 to 7:00 PM.

Lunch is usually included or bring-your-own, depending on the operator. The crew provides snorkelling gear; divers should bring or rent their own equipment.

Practical Tips for Visitors

• Season: Boats run from May to October. July and August sailings sell out fast — book at least two weeks ahead.
• Cost: Day trips start at around 70 to 90 EUR per adult; diving packages cost more.
• What to bring: High-factor sunscreen, a wide-brimmed hat, swimwear, a towel, waterproof camera, and motion-sickness tablets if you are prone to seasickness.
• Accessibility: The landing on Illa Grossa involves stepping onto rocks; moderate mobility is required.

Getting There from Hotel Sancho III

Drive or walk to Las Fuentes Marina (10 minutes by car, 25 minutes on foot). Several local operators sell tickets at the marina office or online. Our reception team at Hotel Sancho III can help you compare options and secure your booking.

Complete Your Trip

After a full day at sea, return to Hotel Sancho III and unwind by our Mediterranean-facing pool. Grab dinner at one of the seafood restaurants lining the marina promenade, then fall asleep to the sound of the waves from your sea-view room. The Columbretes Islands are an experience you will talk about for years — and Alcocéber is the perfect base from which to reach them.