You have probably heard of a glass bottom boat. You might have come across submarine tours that take passengers deep underwater. A semi-submarine sits somewhere between the two – and most people are not entirely sure what one is until they step on board.
At Ningaloo Reef in Western Australia, View Ningaloo operates the SubSea Explorer – the only semi-submersible catamaran in the state. It is one of the most accessible ways to see the reef up close, and it suits visitors of all ages and swimming abilities.
This guide explains what a semi-submarine is, how it works, what you can expect to see at Ningaloo Reef, and why it is worth booking.
A semi-submarine – also called a semi-submersible boat – is a vessel that sits partially below the waterline. Unlike a full submarine, it does not fully submerge. The passenger cabin is built below the surface, while the outer hull and engine remain above water.
Passengers board from the jetty at the Tantabiddi boat ramp, then settle into the lower cabin. Once seated, the windows are level with the water. The reef, coral, and marine life pass outside the glass as the vessel moves through the sanctuary zone.
The experience is comparable to snorkelling – without getting wet. No swimming. No mask. No fins. You simply sit and watch.
A glass bottom boat has windows in the floor of the hull. Passengers look down at the reef below. The viewing angle is limited to what sits directly underneath the vessel.
The SubSea Explorer works differently. It has 16 large glass windows positioned on the sides of the hull, below the waterline. Passengers look outward at 360 degrees – more like looking through a window than peering down through a floor. The range of what you can see is considerably wider.
A full submarine dives completely below the surface and moves through deeper water. A semi-submersible submarine stays at the surface. The engine and upper deck remain above water at all times.
There are no pressure changes and no depth requirements. It is a surface vessel with an underwater viewing cabin. The design also reduces the motion that causes seasickness, making it more comfortable than a standard open boat for guests who are prone to it.
The SubSea Explorer is purpose-built for reef viewing. It is the only semi-submersible catamaran operating in Western Australia.
The lower deck seats guests in carpeted, sheltered space protected from sun and wind. A five-tonne water ballast keeps the vessel stable on the water. The 16 large glass windows give an unobstructed view on both sides of the hull.
Onboard marine biologists provide live expert commentary on every departure – covering the reef ecosystem, marine history, and what guests are seeing through the windows in real time. The vessel holds up to 30 guests, with reduced numbers on the Half Day tour for a more personal experience.
All tours depart from the Tantabiddi boat ramp, a 25-minute drive from Exmouth town centre through Cape Range National Park. A national park day pass is required for guests driving independently.
View Ningaloo is based at Shop 3/2 Ross St Mall in Exmouth. The team can advise on transport options to the ramp for guests who prefer not to drive.
The SubSea Explorer operates in the Tantabiddi Sanctuary Zone – one of the most protected sections of the Ningaloo Marine Park. The result is a reef in noticeably better condition than lower-protection areas of the park.
What you see on any given day depends on conditions and timing. The Tantabiddi area consistently produces strong sightings throughout the year.
The onboard marine biologists identify species and explain what guests are seeing as the tour unfolds. Sightings cannot be guaranteed, but the crew knows the best locations within the sanctuary zone for each type of encounter.
View Ningaloo does not offer whale shark tours. The SubSea Explorer explores the inside of the Ningaloo Reef, within the Tantabiddi Sanctuary Zone. Whale sharks are found on the outside of the fringe reef – a different area entirely.
If you are specifically looking for whale shark tours, View Ningaloo recommends contacting Ningaloo Discovery or Ocean Eco Adventures.
Coral coverage and fish activity remain strong year-round. Some species follow seasonal patterns. From July to October, humpback whales pass through the waters around the North West Cape on their annual migration. The SubSea Explorer regularly spots whales from the upper deck on the way to and from the tour site during this window.
For more on what marine life is active at different times of year at Ningaloo, see our guide to Ningaloo Reef marine life tours.
View Ningaloo offers three reef tour options on the SubSea Explorer, all departing from Tantabiddi with live expert commentary from onboard marine biologists.
Wetsuits are not supplied. Contact Tom at Exmouth Surf Centre for 24-hour wetsuit hire. Personal snorkelling equipment is welcome on board – label it clearly with your name.
Tour pricing is updated regularly and is best confirmed directly before booking. The booking page shows current availability across all three tour options.
Check current prices and book your spot on the View Ningaloo semi-submarine booking page. The team is also available by phone from 7am to 9pm, seven days a week, to answer any questions before you commit.
This format removes the barriers that stop many visitors from seeing the reef at all. It works for a much wider range of people than a standard snorkel tour.
There are no strict age restrictions on any tour. The 1 Hour Coral Viewing tour suits families with very young children or elderly guests who prefer a shorter experience. The 2 Hour tour is specifically structured for young families including babies – broken into sections so there is always something happening to keep young children engaged.
Toddlers should not snorkel independently, but they can enjoy the coral viewing and shallow water play under parental supervision during snorkel stops.
For more detail on which tour suits different age groups, see our family-friendly guide to Ningaloo Reef tours.
Most reef experiences at Ningaloo require snorkelling. The SubSea Explorer removes that requirement entirely. Non-swimmers get the full reef view through the windows alongside everyone else on board.
On the 2 and 3 Hour tours, snorkelling is available but not compulsory. Non-swimmers stay on board for the coral viewing sections while others snorkel, then everyone comes back together. No one misses out.
Boarding involves stepping down into the lower cabin from the jetty. Once seated, the experience is entirely passive. No physical exertion is required at any point.
A toilet is available onboard. Changing facilities are basic – most guests find it easier to arrive in swimwear with a cover-up for the drive to and from the reef.
If you have never seen a coral reef before, the 1 Hour Coral Viewing tour is a low-barrier starting point. The marine biologist commentary gives you the context to understand what you are looking at. Many guests return on a later day to add snorkelling, having built confidence from the first experience.
Both options let you see the Ningaloo Reef in detail. The right choice comes down to your group.
If you are comfortable in the water and want to be physically inside the reef environment, snorkelling gives you a closer, more immersive experience. You move through the coral, get face to face with fish, and set your own pace.
If you are not a strong swimmer, travelling with babies or toddlers, or prefer to stay dry, the SubSea Explorer delivers an impressive reef experience with none of the physical requirements. It is also the better option on days when weather makes open-water swimming less comfortable.
Many visitors combine both. The 2 and 3 Hour tours include semi-submarine viewing and guided snorkel sessions in a single outing.
Not sure which suits your group? Our Ningaloo Reef snorkelling vs viewing guide compares both options in detail.
The Tantabiddi Sanctuary Zone is a no-take, high-protection section of the Ningaloo Marine Park. The reef here has recovered and thrived in a way that is visible through the SubSea Explorer windows.
Coral coverage at Tantabiddi is dense and diverse. Fish populations are high. Turtles and sharks are resident rather than passing through. View Ningaloo operates exclusively in this zone – a deliberate choice that consistently produces better sightings than tours in lower-protection areas of the park.
For a detailed breakdown of what lives in Tantabiddi, see our guide to Tantabiddi Sanctuary Zone marine life and coral gardens.
Here is what View Ningaloo recommends bringing on the day:
View Ningaloo runs tours on the SubSea Explorer throughout the year. All tours are fully licensed within the Ningaloo Marine Park and are open to guests of all ages. No swimming experience is required for the 1 Hour Coral Viewing tour.
The team is based at Shop 3/2 Ross St Mall, Exmouth, and is available by phone from 7am to 9pm, seven days a week.
Book your semi-submarine tour at Ningaloo Reef and secure your spot before the season fills up.
A tour like this is one of the most accessible reef experiences in Australia. It removes the physical barriers that stop many visitors from seeing a coral reef – no swimming ability needed, no fitness requirement, no minimum age.
At Ningaloo Reef, the SubSea Explorer places that experience inside one of the healthiest marine environments in the southern hemisphere. The marine life density at Tantabiddi, combined with live expert commentary, makes for a worthwhile outing regardless of who you are travelling with.
For most groups, the 2 or 3 Hour combined tour gives you both the underwater viewing and a guided snorkel session in one day. For families with very young children, non-swimmers, or anyone wanting a shorter visit, the 1 Hour Coral Viewing tour is a clear and straightforward way to see the reef properly for the first time.
