Which Reef Is Best? The Difference Between Outer Great Barrier Reefs And Inner Great Barrier Reefs In Australia?

After receiving information on the various overnight boat tours, many people ask us to define the difference between the ‘inner’ Great Barrier Reef and ‘outer’ Great Barrier Reef tour options. We’re also asked, which reef is best?

Here, we’ll try to give an insight into the difference between inner Great Barrier Reef liveaboards and outer Great Barrier Reef liveaboards, to help you decide which is the right option for you. We’ll discuss the best starting points for the different reef tours as well as the marine life to be found and other interesting facts about inner vs outer reefs.


Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Green Sea Turtle

The Outer Great Barrier Reef

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Outer Great Barrier Reef

See the Great Barrier Reef in all its glory. The picture-perfect postcard shots that we conjure when we think of the Great Barrier Reef are found when snorkelling or scuba diving on the outer Great Barrier Reefs. The outer Great Barrier Reefs are widely acknowledged as having the most beautiful aquatic life in comparison to inner, coastal reef systems.

Fish, marine mammals and coral thrive on the outer reefs where visibility is often optimal, and water nutrients are abundant. As the name suggests, outer reefs lie further away from shore than the inner reefs – nearer to the continental shelf of Australia.

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Incredible Marine Life on the Outer Reef

The outer Great Barrier Reefs boast far superior water clarity compared to the inner reef, with average visibility ranging from 10 – 40 meters (compared to an average of 5 meters around coastal equivalents). Remarkable biological diversity of marine creatures live on outer Great Barrier Reef systems, with over 1400 types of fish, 130 varieties of sharks and rays and over 600 types of hard and soft corals. Water nutrients are excellent here, resulting in mass fish numbers congregating to feed in the rich oceanic areas.

A common misconception is that outer reef locations are suitable only for advanced snorkelers or scuba divers – and this couldn’t be further than the truth. Outer Great Barrier Reefs offer fantastic, protected, shallow lagoons areas that are appropriate for all levels of diving and snorkelling activities. While some areas of outer reefs do offer dramatic drop-off vistas to advanced guests, these are usually a short distance away from the main vessel.

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Barramundi Cod

All our tours that market themselves as trips to ‘outer Great Barrier Reef locations’ ensure the best locations are visited each day – depending on the weather and time of year – to provide optimal snorkelling and scuba diving conditions to all guests. Unless we advertise as suitable only to advanced scuba divers – all of our outer reef tours offer excellent snorkelling and diving opportunities, catering to all levels of swimming ability and in-water experience.

Photography lovers adore the underwater vistas beneath the surface as well as the sheer beauty of the expansive Coral Sea. Dusk and dawn boast spectacular sunset and sunrise opportunities to capture the perfect shot, while the white, crisp waves on the windward side of the reef highlight the spectacular ‘barrier’ that it is – separating the ocean currents from the protection of the calm reef lagoon areas.

It is the outer Great Barrier Reefs that people imagine when they visualise dramatic and exotic coral formations, teaming with schools of tropical colourful reef fish.

Where is the best place to visit the Outer Great Barrier Reef?

There is indeed a big difference between visiting the outer reef, with a starting point of Far North Queensland compared to a starting point of Southern Queensland.

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Outer Great Barrier Reef Tours

Cairns, in Far North Queensland, is arguably the best place to begin your outer reef liveaboard tour. Cairns is the closest City to the outer Great Barrier Reefs – making the journey time to reach each location ideal. Most tours that depart from Cairns for the outer Great Barrier Reef take approximately 90 minutes to reach their first reef location. This ease of access – and short distances between the different northerly reef sites – means that you get to spend longer at each spectacular location.

Boat tours that visit the most beautiful outer Great Barrier locations are usually higher speed catamaran vessels – designed to give guests stability and comfort on outer reef voyages.

We don’t recommend starting your outer Great Barrier Reef liveaboard from areas in Southern Queensland. While Airlie Beach and the Whitsundays are perfect for inner reef sailing liveaboards – the distance to the outer reefs makes them less appealing from these starting points. Most of the vessels in these areas are designed as sailing vessels – catering to beach and island reef cruises.

The Inner Great Barrier Reef

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Fitzroy Island on the Inner Great Barrier Reef

The inner Great Barrier Reef systems lie close to the coastline of Queensland Australia and comprise of fringing reefs and pristine, idyllic sand islands.

Inner reefs often are home to a wide variety of soft corals and are a nursery for smaller fish before they mature and venture further out. The inner reef ecosystems also have seagrass meadows, which form an essential breeding ground for many species of aquatic life. The islands are safe havens which protect from weather and larger predators to species of small fish and juvenile mammals.

Inner fringing reefs provide excellent snorkelling and swimming opportunities, with sheltered bays often having calm swimming areas. Access to snorkelling and swimming is usually directly off the beach, making easy entry and exit points, although some locations will require boat access.

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Whitsundays Inner Great Barrier Reef

Water visibility at inner barrier reefs is not as clear as outer areas, with an average visibility of around five meters (or sixteen feet). This is mostly because of the amount of sand in the water from the nearby coast and islands. The lesser visibility is offset by the fact that the inner reefs are located in much shallower depths than the outer reefs. As you are snorkelling relatively closer to the ocean bed, there’s still plenty to see as you enjoy your time in the water.

Inner reefs are ideal destinations for beginner snorkelers and non-swimmers or those who are looking for a relaxing beach getaway. Shallow, calm, protected water with easy beach access is optimal for those who want the best of both worlds – the option to go for a swim plus the leisure time to spend on idyllic sand islands in tropical blue water.

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Green Island on the Inner Reef

From the inner reef sand-islands, there are often other activities available to non-swimmers and those who don’t want to spend a lot of time in the water. Glass-boat tours and semi-submarine tours are popular options for those who don’t want to get your toes wet. Check your tour itinerary to see if these are available options on the Great Barrier Reef liveaboard you choose.

Where is the best place to visit the Inner Great Barrier Reef?

Inner Reefs from the Whitsundays in Arlie Beach, Queensland
The picturesque islands of the Whitsundays, from Airlie Beach in Queensland, are home to some of the best fringing reefs found on throughout the Great Barrier Reef region. Inner, coastal reef systems surround the Whitsunday Islands, and many provide ideal, shallow snorkelling and swimming areas that are well protected from the weather by the islands.

If you are embarking on a Whitsundays Great Barrier Reef liveaboard, we recommend that you enjoy a sailing liveaboard around the inner reefs and islands – and revel in the scenic mountain landscapes, white sandy beaches, and shallow snorkelling. As the vast majority of liveaboards in the Whitsundays are sailing boats, they are ideally suited for the inner reef, with comfortable and well-sheltered island cruising.

(While it is possible to visit the outer reefs from the Whitsundays, there are better places for visiting outer snorkelling and scuba diving destinations. The extended journey time from the Whitsundays to the outer reefs makes them less accessible than from other more convenient departure points, such as Cairns in Far North Queensland.)

Inner Reefs from Cairns, Far North Queensland
From Cairns, the most popular inner reef destinations are Green Island, Fitzroy Island and the Frankland Islands. These spectacular reef destinations are accessible by fast island ferries and are predominantly day trips.

For those who want the overnight island experience from Cairns, it is possible to sleep on the island itself – at Green Island Resort. Island resorts are luxury hotels with full hotel amenities.

If you are in Cairns to enjoy an outer Great Barrier Reef liveaboard tour, adding an inner reef island day trip onto your itinerary is an excellent addition to your Cairns visit. You’ll get an enjoyable experience of a different Great Barrier Reef ecosystem.

There are a small number of overnight sailing liveaboards that depart from Cairns which stop at more remote and untouched sand islands. This sailing liveaboard from Cairns visits both inner and outer Great Barrier Reef locations on a two day, one-night liveaboard. (Please note that the exact itinerary varies each trip due to weather conditions).



What animals can be found, and where?

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Green Sea Turtle

Some larger mammals, such as dugongs, inhabit the areas of shallow inner reefs and warm coastal waters. As the only marine mammal that is 100% herbivore, dugongs feed on the seagrass floor – however, sightings are rare as their numbers in the wild are low, and they are considered an endangered species.

Fish may be found congregating in large numbers on the outer barrier reefs, where water nutrients are optimal and life is plentiful. So many different species of fish may be sighted on the outer reef walls that there are too many for us to list here. Some of our favourites include schools of oriental sweetlips, red bass, paddle tail snapper and Napoleon Maori wrasse. Outer reefs are known for such abundant marine life that tropical fish of every colour, size and shape may be seen amidst the myriad of hard and soft corals carpeting the limestone structure of the reef formations.

Other large creatures that most liveaboard enthusiasts would love to see – such as turtles, dolphins and rays are equally as common to be spotted swimming in the areas of inner reef and islands as they are on the outer reef. Generally speaking, the further north your departure point, the more of these animals you are likely to come across.

Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Giant Clam

Our advice to encounter these incredible animals is to spend as much time as you can snorkelling, swimming or scuba diving! Glass bottom boat tours are another way to spend time in the water, even if you don’t feel like getting wet. This dramatically increases your chances! There are also optimal times of the day for chance encounters with certain species of marine life – which is why a Great Barrier Reef liveaboard tour beats a day trip, hands down, for animal encounters every time.

Sharks are more commonly seen at night, with dusk and dawn also active shark times. Scuba divers can go night diving on most of our Great Barrier Reef liveaboards and is probably one of the most incredible life experiences – if that’s your kind of thing!

Turtles are most active at dawn and in the earlier hours of daylight – although they may be seen at all hours of the day and even sleeping during the night!

Humpback whales are seasonal to the Great Barrier Reef – with the winter months of June to September being considered optimal times to catch a sighting. This is generally when these beautiful creatures are migrating into warmer waters along the east coast of Australia. Boat crews, however, are reporting that the times of year that whales have been sighted between reefs are fluctuating quite a lot in recent years. This is largely due to the changing global ocean climates altering their usual migration patterns.

Which Reef Is Best?

When choosing your Great Barrier Reef liveaboard tour, consider whether you are on an adventure to see the best fish, coral and marine life possible or whether you are seeking an idyllic, relaxing beach/island getaway in a tropical paradise.

The inner Great Barrier Reefs of the Whitsunday Islands – located off Arlie Beach in Southern Queensland and the outer Great Barrier Reefs located out of Cairns in Far North Queensland offer impressive encounters with this incredible part of Australia and its famous natural wonder.

We hope we’ve provided you with a clear overview of the differences and similarities between these two reef ecosystems, to help you choose the best overnight liveaboard tour for yourself, family and friends.

We recommend you experience both and please send us your feedback on where you feel is the very best place for visiting Australia’s Great Barrier Reef!


Which Reef Is Best? Outer Great Barrier Reef vs Inner Great Barrier Reef tours
Eastern Clownfish