Adventure Bay is the great sweep of sand and rock on South Bruny's east coast, a place steeped in exploration history: Tobias Furneaux anchored here in 1773, James Cook in 1777 and William Bligh in 1788 and 1792, and the bay became an early whaling base. For divers it is the hub of Bruny Island, offering both easy shore dives and boat access to the more dramatic sites of the east coast. The Marine Life Network guide documents several dives around the bay.

Quiet Corner, a sheltered spot with a thick Macrocystis garden, holds the iron ribs and anchors of the barque Natal Queen, wrecked in 1909; Penguin Island near the bay's southern end has a narrow, steep reef and shallow sea caves; and further south, Cape Connella and the waters beneath Fluted Cape have larger rocks and deeper, luxuriant seaweed. Typical reef fish include blue-throated and purple wrasse, leatherjackets, magpie and banded morwong and bastard trumpeter, and weedy seadragons shelter in the weed. The guide notes that the shallow reefs are heavily fished and speared, so fish can be wary near shore.

Because the bay faces east, it is sheltered from the prevailing westerlies and often calm when the channel side of Bruny is choppy. There is no dive shop or air on Bruny, so bring filled cylinders from Hobart. Adventure Bay has accommodation, a store and cafes, and the Fluted Cape walk gives superb views over the bay and the sites below.

It is an ideal base for a diving weekend combining shore and boat dives.

Bruny Island is reached by the vehicle ferry from Kettering (about 35 km, 40 minutes south of Hobart via the Southern Outlet and Channel Highway) to Roberts Point on North Bruny; the crossing takes about 20 minutes and runs frequently, but book or queue early in summer. From Roberts Point drive south across The Neck to Adventure Bay (about 35-40 minutes), where there are boat ramps and a jetty. There are no dive shops or air fills on Bruny – bring filled cylinders from Hobart or Kingston.

Shore entries are found along the bay's rocky ends, including the Quiet Corner area near the bay's northern end and the rocks below Fluted Cape at the southern end near the Grass Point walking track. Most sites need only a short walk from roadside parking; outer sites such as Penguin Island, Fluted Cape and Cape Connella are a 5-20 minute boat run from the Adventure Bay ramp.

Adventure Bay faces east into the Tasman Sea and is sheltered from westerly and south-westerly winds, so it is often calm when the channel side is choppy. Easterly and north-easterly winds and swell make the bay and the outer sites rough; southerly groundswell wraps around Fluted Cape and Cape Connella. The Marine Life Network notes that swell reduces visibility and strips delicate growth from the shallow reefs.

Best after several days of westerlies; late summer and autumn are the most reliable. Heavy rain has little effect except near creek mouths.

For a shore dive, enter at a sheltered rocky end, follow the reef edge through the kelp at 4-10 m and return along a shallower contour. By boat, drop beneath Fluted Cape and follow the dolerite wall to 20-25 m before rising through the kelp.

No scheduled dive operator on Bruny; Underwater Adventures Tasmania runs South Bruny and Channel boat trips from Hobart; otherwise private boats from Adventure Bay. Pennicott Wilderness Journeys (Bruny Island Cruises) visits the coast by boat for sightseeing, not diving.