The northern coast of Rocky Island is exposed to the prevailing north wind and swell, making the surf zone along the rugged shoreline extremely rough at times. The dive is definitely not suitable for novices. Divers should be aware that boat pickup is often impossible along the north coast, and they may have to swim through rough surface waves to the calmer waters round the reef corner for pickup.

These caveats aside, Rocky’s north coast is a fantastic dive, with absolutely sheer vertical walls and rugged, jagged profile. Strong currents can make this a bullet-like drift dive, and the strong surge can often be felt even at 25m (80ft) or more. With a big swell running, the upper 8 to 10m (26-33ft) of water inshore is churned like a washing machine.

The reef composition is generally stony, with fairly good coral cover. The upper 20m (65ft) is particularly dense, and the entire north reef wall is covered in soft corals, making it perhaps the best soft coral site on the island. Fish life is rich and varied, with a strong bias toward the schooling species. Reef fishes are also well represented. In particular, very large groupers and Napoleon wrasse are common. As in the rest of the island, sharks are always a tantalizing possibility.