Ricketts Point is Melbourne's marine sanctuary, 115 hectares of shallow sandstone reef, seagrass and sand along the Beaumaris foreshore that was protected in 2002 and has since become the most visited snorkelling and shore-diving area in the city. Geologically it is the seaward edge of the Beaumaris sandstone, the same fossil-rich rock as the Red Bluff cliffs, worn into a series of flat intertidal platforms, low points and small sea caves with channels and gutters between them. Depths are slight: reef tops sit at 1 m or are exposed at low tide, the channels run 2-4 m and the outer reef edge drops to sand at 4-8 m.

Within that small range there are eight recognised entry points and dive areas, each documented separately in this database: Quiet Corner (McGregor Rock) and Banksia Point at the north-west end, Tea House Reef North and South and Tea House Bay in the centre around the yacht club and teahouse, Middle Reef and Triangle Reef off the life saving club, and Table Rock at the south-east end with the Sea Scouts Jetty just outside the boundary. Because it is a no-take zone the fish are tame and numerous: schools of juvenile snapper and zebrafish, old wives and moonlighters under ledges, dusky morwong, scalyfin defending algae patches, blue-throat wrasse, blennies in every crevice, and rays, banjo sharks and Port Jackson sharks on the sand. Octopus are common, and seagrass patches hold seahorses and pipefish.

It is above all a beginner's and a night diver's place; the shallow depth, easy sand entries, lights, toilets and cafes mean it hosts more training dives, try-dives and club night dives than anywhere else on the bay. Experienced divers use it as a critter and photography site and as the reliable fallback when the peninsula is blown out. The Marine Care Ricketts Point volunteer group runs guided snorkels and monitors the reef, and the sanctuary is patrolled; leave everything where it is.

Take Beach Road south through Sandringham and Black Rock to Beaumaris, about 35 minutes from the CBD. The sanctuary runs along the shore for 3 km and has car parks at Quiet Corner (Central Avenue), the Beaumaris Yacht Club (off Beach Road, ticketed), the Ricketts Point Teahouse (ticketed) and the Beaumaris Life Saving Club, plus street parking in Coronet Grove and Rennison Street for the northern and southern ends. Most divers use the yacht club car park and enter from the sand directly in front of the club, a 50 m carry, which gives access to Tea House Reef and the sanctuary's central reefs.

Steps lead down from Beach Road at Coronet Grove (Banksia Point), Central Avenue (Quiet Corner) and east of Rennison Street (Table Rock).

Best with offshore light northerly to south-easterly winds. Avoid moderate to strong onshore southerly through westerly to north-westerly winds, which raise chop across the shallow reef flats, stir the sand and make the rock entries unpleasant; if you see white water over the reef from Beach Road, go elsewhere (Quiet Corner is the fallback). Dive just before high tide for the clearest water and enough depth over the reef top, which is exposed or awash at low water.

Visibility 3-8 m on a good day, better in winter, poor for two or three days after rain. No swell. Boat traffic outside the swimming zone is constant in summer, so tow a flag.

Enter on the sand in front of Beaumaris Yacht Club, fin out toward the double markers, then turn left (south) and work along the channels of Tea House Reef at 2-4 m, out to the reef edge at 4-5 m where it meets sand, then return along the same reef toward the yacht club. Turn at half gas or 30 minutes and finish in the shallows off the club beach. At night stay within the reef channels for easy navigation.

No commercial dive boat – shore site dived independently and by Melbourne dive shops for training and night dives (Scuba Culture in Cheltenham is the closest shop and uses the sanctuary regularly; Aquability and Melbourne Diving Services run club nights). Marine Care Ricketts Point runs guided snorkels in summer and Parks Victoria licensed tour operators run snorkel tours.