Port Douglas: Great Barrier Reef Snorkeling & Diving Cruise

★★★★★★★★★★ 4.64 (111 reviews) 84% rated it 5 stars

Free cancellationTravelers' pickLikely to sell out

1/7

Duration8h

GroupUp to 65

LanguagesEN

Mobile ticketAccepted

Three Agincourt Reef Sites, One Day, Small Groups

You board a small-group catamaran in Port Douglas, visit three outer reef sites with a marine biologist guide, and choose between snorkeling with a guided tour or up to three certified dives. Lunch, morning and afternoon tea are included, as is hotel pickup. The day runs full but the boat's design and capped numbers mean it never feels rushed or crowded.

Step-by-step itinerary

Snorkeling and diving at Agincourt Reef

Depart from Port Douglas on Poseidon
Visit three snorkeling and diving sites
Certified divers do up to three dives
Snorkelers join guided reef tour
Attend reef interpretation talk
Enjoy morning tea and buffet lunch
Relax on air-conditioned saloon and deck
Participate in marine monitoring survey

The Experience

Most reef boats from Port Douglas pack you in tight and hit the same popular sites everyone else does. Poseidon does the opposite — the catamaran holds just 65 people, and it has a special permit to access the outer Agincourt ribbon reefs where the coral and fish density shift noticeably. You leave Port Douglas in the morning and spend the day moving between three different spots, each one chosen based on conditions and what the marine biologist spots that day. If you're a certified diver, that means up to three separate dives into the gardens themselves. If you're snorkeling, you get a guided tour with the same biologist, who talks you through what you're actually looking at instead of just pointing.

The boat itself matters more than it sounds. It's built for this — a lowering transom so you're not scrambling down a ladder in fins, an air-conditioned saloon when the sun gets too much, and open deck space that doesn't feel crowded. Introductory diving is available if you've never done it but want to try, and the minimum age for scuba is 12. Snorkelers get the same reef interpretation talk as divers, then a separate guided tour so you're not just floating alone trying to figure out what's a parrotfish. The marine biologist also runs a monitoring survey — you're actually contributing data while you're down there, which sounds like work but mostly just means you're paying attention to what the reef looks like that day. There's also a standing permit for dwarf minke whale encounters if they show up, which doesn't happen every day but when it does, it changes the whole trip.

Morning tea, coffee and focaccia come with boarding. Lunch is a buffet with prawns, and afternoon tea rounds it out — you're not getting hungry or thirsty. Hotel pickup and drop-off are included if you're staying in the Port Douglas area, so you don't have to arrange transport or figure out where the marina is. Bring your own towel, swimmers, sunscreen and a hat; the boat provides snorkeling gear. If you're diving, remember the flying rules — 12 hours minimum after one dive before you fly, 24 hours if you do multiple dives, because altitude matters after decompression.

What’s included

Your day includes hotel pickup and drop-off in the Port Douglas area, guided snorkel tour with marine biologist interpretation, reef interpretation talk at each site, buffet lunch with prawns, morning tea with coffee and focaccia, afternoon tea, snorkeling equipment, and the Environmental Management Charge.
Certified divers can do up to three dives with choice of mooring, drift or excursion dives depending on conditions.
Introductory diving is also available.

Good to know

Moderate physical levelInfant seats availablePets welcomeNot for heart conditions

Operated by The Quicksilver Group

Is this one for you?Right for experienced snorkelers and certified divers who want smaller groups and access to outer reef sites most day boats skip. Plan for a full day on the water — that's what the three-site itinerary and multiple dives need — and bring a moderate level of fitness; the boat and reef work are not strenuous, but the day itself is active.