How Far Is the Great Barrier Reef from Cairns, and How Long Does It Take?
Green Island is about 27 km out, Moore Reef about 56 km. Boat and flight times from Cairns, seasickness tips and how long each trip spends in the water.
The nearest reef islands are about 27 km from Cairns, around 45 minutes by fast catamaran. The outer reef, where most full-day boats go, is further: Moore Reef is about 56 km offshore, roughly 1.5 hours on a fast boat, and most outer reef trips quote 75 minutes to two hours to their first site.
What matters more than the distance is how much of your day you spend in the water once you arrive. That ranges from 1.5 hours on a short half day to six hours on the longest full days.
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Distances and crossing times
| Destination | Distance from Cairns | Time by boat |
|---|---|---|
| Green Island (coral cay) | About 27 km | About 45 minutes |
| Fitzroy Island (granite island) | About 29 km | About 45 minutes |
| Moore Reef (outer reef pontoons) | About 56 km | About 1.5 hours |
| Other outer reef sites (Saxon, Hastings, Upolu, Flynn, Milln and more) | Further out | 75 minutes to 2 hours, depending on boat and site |
| Michaelmas Cay (seabird cay) | Further out than Green Island | About 2 hours on a sailing catamaran |
Almost every boat leaves from the Reef Fleet Terminal at 1 Spence Street or the Marlin Marina fingers beside it, on the Cairns waterfront. Scenic flights leave from Cairns Airport or a heliport by the marina, depending on the operator.
The reef itself is vast, about 2,300 km long with more than 2,900 individual reefs, so “the reef” off Cairns is really a scatter of reefs and cays at different distances. Heart Reef, the famous heart-shaped one, is far to the south in the Whitsundays near Airlie Beach, and neither Cairns boats nor Cairns flights go there.
Travel time against time in the water
This is the table that tells you what you are buying. Times come from each operator’s own itinerary.
| Trip | Out | At the reef | Back | The day |
|---|---|---|---|---|
| Half-Day Snorkelling Tour, $126 | Fast boat | 1.5 hr guided snorkel | Fast boat | 4 hr in all |
| All-Inclusive Half Day, $147 | 1 hr | 2 hr | 1 hr | Noon to about 5pm |
| Premium Half Day, $137 | 1.5 hr | Up to 2 hr | 1.5 hr | 9am to 2pm |
| Silverswift Three Reef Sites, $216 | 80 min | About 5 hr at 3 sites | 75 min | 8:30am to 4:30pm |
| Outer Reef and Coral Cay Cruise, $203 | 75 min | 6 hr at Upolu Reef | 75 min | Full day |
| Full-Day Tour with Lunch, $193 | 80 min | 5 hr at 2 sites | 1.5 hr | Full day |
| Premium Snorkel and Dive Day, $179 | 1.5 hr | Up to 5 hr at 2 sites | 1.5 hr | About 8 hr |
| Premium Catamaran Cruise, $193 | 2 hr | About 4.5 hr incl. lunch | 2 hr | About 9 hr |
| Michaelmas Cay Snorkel, $202 | 2 hr | 4 hr at the cay | 2 hr | Full day |
| Green Island Cruise, $79 | About 45 min | Up to 7 hr on the island | About 45 min | 8:30am or 10:30am start |
Prices are per person in US dollars as GetYourGuide quotes them. Weather and sea conditions can change sites and timings on the day.
What the numbers mean for your day
A half day gives you a real taste of the outer reef for the least time and money. The trade-off is simple: roughly half your trip is spent on the boat. On the All-Inclusive Half-Day Trip, that is two hours in the water out of a five-hour afternoon. Our half-day tours page lines them up.
A fast full day tips the balance firmly towards the water. The Silverswift Three Reef Sites tour takes 80 minutes to reach its first site, then spends around five hours across three outer reef sites, with only ten minutes between each, and a guided snorkel with a marine biologist at the last. Divers can fit up to three dives. It is back at the Reef Fleet Terminal by 4:30pm. The Outer Reef and Coral Cay Cruise goes further still with six hours at Upolu Reef on a 75-minute crossing.
A slower boat makes the ride part of the day. The Premium Catamaran Cruise takes about two hours each way on a sailing catamaran, with morning tea on the way out and the sails up on the way home when conditions allow. You get around four and a half hours at the reef, lunch included, and a gentler pace.
An island trip is the shortest crossing with the most time at your destination. Green Island and Fitzroy Island are both about 45 minutes away, and the full-day trips give you up to seven hours to snorkel from the beach, walk and swim. The reef around the islands is inner reef, closer to shore. See the Green Island and Fitzroy Island pages.
Getting there by air
A scenic flight is the quickest way to reach the reef. The Outer Edges Scenic Flight (our breakdown) is over Green Island within about ten minutes of leaving Cairns, then continues over Arlington Reef, Oyster Reef and Upolu Reef on a 30- or 40-minute flight. The 40-Minute Window-Seat Scenic Flight (our breakdown) leaves from Cairns Airport, and the 30-Minute Helicopter Flight (our breakdown) from Marina Point on the Cairns waterfront. Our scenic flights page compares them.
Seasickness on the crossing
The outer reef crossing is open water, and on a windy day it can be rough. Reviews on several boats mention choppy rides and seasick passengers, followed almost always by praise for how the crew looked after them. A few things help.
Take your remedy before you board, as the packet directs. Some boats sell travel sickness tablets on board, including the Moore Reef pontoon boat, but by the time you feel queasy it is late to start.
Pick a shorter crossing if you know you suffer. Green Island and Fitzroy Island are about 45 minutes away. The Frankland Islands River, Rainforest and Reef Tour (our breakdown) starts with a coach south and a 30-minute cruise on the calm Mulgrave River before a short open-water crossing to the islands.
Check the suitability list. The fast half-day boats from Reef Adventures and Pure Snorkelling list people prone to seasickness among those they do not suit.
Look at the marine forecast the day before, and book your reef day early in your trip so there is room to move it. Our best time to visit guide covers the seasons.
Frequently asked questions
How far is the Great Barrier Reef from Cairns?
Green Island is about 27 km from Cairns and Fitzroy Island about 29 km. The outer reef sites are further out; Moore Reef, for example, is about 56 km offshore.
How long does it take to get to the Great Barrier Reef from Cairns?
About 45 minutes by fast catamaran to Green or Fitzroy Island, and about 1.5 hours to Moore Reef. Most outer reef boats quote 75 minutes to two hours to their first site.
How long will I spend in the water on a Cairns reef trip?
From about 1.5 hours on a four-hour half day to six hours on the Outer Reef and Coral Cay Cruise. Most full days give you around four to five hours at the reef.
Can you see the Great Barrier Reef from Cairns airport?
Not from the terminal, but scenic flights leave from Cairns Airport and reach the reef within minutes. The Outer Edges Scenic Flight is over Green Island about ten minutes after take-off.
Is Heart Reef near Cairns?
No. Heart Reef is in the Whitsundays near Airlie Beach, a long way south. Cairns cruises and flights do not reach it.
Want the most reef for your crossing? Check availability on the Silverswift, with three outer reef sites in one day.
Two Outer Reef Sites, One Day on a Catamaran
Snorkelling gear and a guided snorkel tour, a chef-prepared lunch, morning and afternoon tea, and a marine life talk on board. Rated by more than 3,800 guests, with free cancellation.
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