FOR the very first time in Australia, tourists will be able to dive to depths of up to 30m below the ocean's surface onboard a fully submersible hybrid tourist submarine.
Down Under Submarines has opened for tours in Mooloolaba on Queensland's Sunshine Coast, and is the only operating submarine of its kind in the world.
What makes the SUBCAT-30 so unique is it is a hybrid vessel, meaning it can both dive underwater and travel on top of the water's surface like a catamaran.
Visitors will be given the opportunity to experience both, with dive experiences and sunset cruises available in the waters off Mooloolaba.
The submarine tours are family-friendly, with children over two years old permitted when accompanied by an adult.
Down Under Submarine director Andrey Alexeenko said the first dive tour would take visitors up to 18 metres below the surface in the waters off Mooloolaba, 1.5 nautical miles out from Point Cartwright.
"As well as the marine life you can spot out the window, travelling in the nearly 20-metre-long submarine is an experience in itself," Mr Alexeenko said.
"It's a one-of-a-kind submarine which has a special hull above the water so passengers can get that experience of both submersion and refloating.
"That's the difference, and it really gives you that adrenalin rush when you see you're starting to submerge."
The SUBCAT-30 - painted a very apt shade of yellow - is also sustainable as it is powered by six battery-operated electric thrusters that produce zero emissions while submerged.
The interior design is similar to that of a plane cabin, with 14 circular windows offering visibility of up to 30 metres underwater and video monitors providing real-time footage of the ocean around you from the four cameras located on the sub's exterior.
During the dive an onboard guide provides commentary about the submarine and surrounding marine life.
The submarine also has an external deck, and on the Yellow Submarine Cruise travellers will be able to walk between the submarine's exterior and interior cabin.
Underwater the SUBCAT-30 travels at around 2 km/h and is extraordinarily manoeuvrable to ensure it never comes into contact with coral reefs or marine life.
The Submarine Dive Experience will have a dive time of around 30 minutes plus 20 minutes surface travel, while the "Yellow Submarine Cruise" will go for an hour at sunset just outside Mooloolaba's main beach or along sheltered canals, depending on the weather conditions.
The Submarine Dive Experience costs $253 for adults and the Yellow Submarine Cruise $55.
Meanwhile passengers aboard the newly launched luxury cruise yacht Scenic Eclipse 11 will be able to enjoy a submarine experience that will take them below the ocean.
Custom-built for optimal sightseeing excursions, Scenic Eclipse II features the new first-of-its-kind Triton 660/9 AVA submarine, with large ultra-clear acrylic spheres designed for optimum underwater viewing.