Dart Reef is a remote oceanic wall site in the Coral Sea, featuring a dramatic drop-off that begins at 25 metres and extends to depths exceeding 400 metres. This site is strictly for advanced divers due to the significant decompression obligations and deep-water environment. Visibility is exceptional, ranging from 30 to 100 metres. While currents are generally mild, they can shift, and divers must manage risks including nitrogen narcosis and decompression. Access is exclusively by boat, located 110 kilometres from the shore. Divers should carry a surface marker buoy and redundant dive computers to navigate the challenging conditions of this deep-water reef.

Rock Arch at Flinders Reef offers a complex topography featuring a dramatic wall, a cave system, and reef structures. Divers can explore depths ranging from 5 to 40 metres, with an average depth of 25 metres. The site is accessible only by boat and is suited for advanced divers due to the overhead cave environment and significant depth. Visibility is high, typically between 30 and 60 metres, though currents remain mild. The reef supports a variety of reef fish and invertebrates throughout the structure. Divers should carry a torch for the cave sections and monitor air consumption closely given the depth and overhead hazards.

Herald Surprise is a wall and reef site in the Coral Sea, offering depths reaching 70 metres. The vertical wall structure is colonised by soft corals, sponges, and sea fans. Divers experience consistent visibility of 30 metres, though the remote, exposed location means conditions can be unpredictable. This site is suited for advanced divers capable of managing decompression dives and strong currents. Access is by boat only. Divers should carry a reef hook for use along deeper sections of the wall and confirm decompression gas availability with their operator before departure. The site supports a variety of reef fish and invertebrates typical of the region.