Lawrence Rocks are two steep volcanic islets rising to 60 m about 2 km south-east of Point Danger at Portland, capped with guano and home to one of the largest Australasian gannet colonies in Australia – around 6,000 pairs that nest from September to April and spill over onto the mainland at Point Danger, the only mainland gannet colony in Australia. Australian fur seals haul out on the ledges. Underwater the rocks fall away in walls, boulder slopes and ridges to sand at 24–30 m on the exposed southern and eastern faces, and Visit Portland describes the site in terms of stunning natural architecture, abundant marine life and kelp forests. The steep faces in cold upwelled water carry heavy sponge and ascidian cover with gorgonians in the deeper shade, the boulder crevices are full of crayfish and abalone (which are taken on the northern side), and the water column holds schools of sweep, butterfly perch and salmon, boarfish and blue devils under the ledges, and seals throughout. The gannets diving through the surface on a calm day are a spectacle in themselves.

The rocks divide naturally into two kinds of dive. On the exposed sides are the deep walls, the premier boat dive of the Portland area, requiring calm weather and Advanced Open Water depth and experience. On the sheltered northern and north-eastern side, in the lee, are a cluster of shallower sites – North Point, The Saddle, The Nursery with its sea caves, and the scuttled trawler Emily S – recorded separately, which can be dived on far more days and by Open Water divers. No dive charter operates from Portland, so access is by private boat or arrangement with a fishing charter, and that keeps the walls lightly dived. Together with Julia Percy and Cape Bridgewater the rocks make Portland the best base for big-animal and wall diving in western Victoria, given the weather.

Boats launch at the Portland Harbour ramps on Lee Breakwater Road (North Ramp and South Ramp), both with trailer parking, inside the harbour breakwaters. From the harbour run south past Point Danger to Lawrence Rocks, about 8 km and 20 minutes in a small boat. The sheltered sites (North Point, The Saddle, The Nursery, Emily S) are on the northern and north-eastern side; the deeper walls are on the exposed southern and eastern faces and are only approached in calm weather.

Boats must keep well clear of the gannet colony and seals hauled out on the rocks. Portland SCUBA in town supplies air; no dive charter operates from Portland, so trips are by private boat or arrangement with fishing charters.

Lawrence Rocks stand 2 km offshore in the open Southern Ocean south-east of Portland and the deep walls face south and east into the swell. Visit Portland describes the diving as weather dependent with good conditions meaning a low swell and light northerly winds; the exposed faces need swell under about 1 m, while the northern lee sites are workable to about 1.5 m. Southerly and easterly winds and any big swell put the whole site out.

The Bonney Upwelling (November–April) brings cold, nutrient-rich and sometimes green water; autumn is clearest. Current runs around the rocks on the tide and can be strong in the gap. Diveable perhaps 40–60 days a year, mostly on the lee side.

Anchor on sand off the southern or eastern face in 20–25 m on a calm day, descend the line and follow the wall and boulder slope with the rock on one side, working through the kelp and along the ledges at 18–25 m, then ascend gradually along the wall to a safety stop in the shallows where the seals play. Turn at a third of your gas and return to the anchor; in current, plan a drift with the boat following.

No dedicated dive charter operates from Portland. Portland SCUBA (PADI centre) runs courses and occasional day trips; local fishing charters take divers by arrangement; Portland dive club members use private boats. Warrnambool Diving visits occasionally.