Poseidon Outer Reef Cruises

Premium day trips from Port Douglas to three Agincourt Ribbon Reef sites with marine biologist on board, diving, and snorkelling for up to 60 guests.

Poseidon Outer Reef Cruises is a premium day trip operator departing from Port Douglas to the Agincourt Ribbon Reef system on the outer edge of the Great Barrier Reef. The Agincourt Reefs represent some of the most pristine and biodiverse sections of the entire reef system, benefiting from their location at the continental shelf edge where clear oceanic water delivers exceptional visibility often exceeding twenty-five metres.

The Poseidon vessel visits three different Agincourt Reef sites on each trip, providing more variety than most other day trip operators in the region. Each site is carefully selected based on current conditions to maximise marine life encounters and coral viewing. Typical sightings include green and hawksbill turtles, whitetip and blacktip reef sharks, giant clams, Maori wrasse, barracuda schools, and an extraordinary density of tropical fish species among healthy staghorn and plate coral formations.

The operation carries a maximum of 60 guests with a high crew-to-guest ratio, ensuring personalised attention for both divers and snorkellers. Certified divers enjoy up to three dives with all equipment provided, while introductory dives are available for beginners. A marine biologist is on board every trip to provide educational reef presentations and guided snorkel tours. The vessel features a spacious sundeck, fresh tropical lunch buffet, and complimentary tea and coffee throughout the day. Port Douglas departures offer the advantage of a shorter transit time to the outer reef compared to Cairns.