Harmers Haven is the tiny holiday settlement west of Cape Paterson at the end of a dead-end road, fronted by what the Bass Coast diving and snorkelling guide calls a very rocky beach suited to experienced snorkellers, where the marine life is crustaceans and molluscs and the ledges are sharp with limpets and mussels, so boots and gloves are recommended. It is not a scuba destination in the conventional sense but a rock-platform exploration in 2–8 m for divers and snorkellers who like working the gutters of an exposed coast. The platforms are the same Cretaceous sandstone as the Bunurong coast, cut into gullies, pools and undercut ledges, and at high tide on a flat day the gullies fill with clear water and become channels to follow out to the reef edge, where kelp, coralline algae and sponge cover the rock and crayfish, abalone, crabs, shrimp and sea stars occupy every crevice; wrasse, zebrafish, leatherjackets, sweep and juvenile morwong move through the gutters and stingarees lie in the sand pockets.

The coast here is a ships' graveyard: the wooden barque Artisan was wrecked on the adjacent Wreck Beach in 1901 and its remains are a shore dive in their own right, and the Bass Coast's historic coal-mining shoreline runs west to Kilcunda. Harmers Haven is outside any marine park, so fishing and collecting are legal within the regulations, and it is used more by spearfishers and cray divers than by sightseeing divers. Its appeal is solitude and rugged coast; its price is the rocky walk, the sharp ledges and a weather window that is narrower than at Cape Paterson's Bay Beach a few kilometres east.

For experienced platform divers on a flat morning it offers uncrowded, life-rich gutters and a piece of coast few divers bother with.

From Wonthaggi take Cape Paterson Road south and turn right onto Harmers Haven Road (about 10 km from Wonthaggi, 2 hours from Melbourne); the road ends at a small car park above the beach. Walk down onto the very rocky beach – 5 minutes over boulders and ledges, boots essential – and enter through a gully in the platform at high tide in small swell. Wreck Beach and the Artisan wreck site (a separate shore wreck dive) are a short walk east along the coast.

The Bass Coast guide's advice is that Harmers Haven suits experienced snorkellers and is best in southerly to south-westerly winds without swell – an unusual recommendation for a south-facing coast that reflects local shelter from the platforms – but in practice it needs a flat sea from any direction, at high tide, and is unworkable in any real south-westerly swell. Early morning. Autumn most reliable.

Enter through a gully at high tide, follow the gutter seaward to the outer edge of the platform at 5–8 m and work along the ledges with the shore on one shoulder; turn at a third of gas because the return is over shallow platform, and exit through the same gully with a hand on the rock.

No dive shop on the Bunurong coast; sites are dived by independent divers and Melbourne/Gippsland clubs (SEADS – South East Australian Dive Society, Dive La Trobe, VSAG). Nearest air fills in Melbourne's south-east or by arrangement in the Latrobe Valley.