The Darlington jetty is where every visitor arrives on Maria Island, and it is also an easy, relaxing snorkel or shallow dive. The Marine Life Network guide rates it 5 out of 10 and describes jetty piles and a small kelp garden in 2-5 m, with anemones, sponges, school fish, Australian salmon, trumpeter and squid, and cuttlefish at dusk. It notes that the site is inside the marine reserve and that divers should check ferry times.

The piles are encrusted with sponges and anemones and shelter schools of small fish, while the sand around them is good for spotting stingarees and flathead. At dusk cuttlefish and southern calamari come in to feed, making an evening snorkel from the campground worthwhile for those staying overnight.

The Tasmanian Scuba Diving Club notes that Maria Island offers both shore and boat diving, and the jetty is the obvious shore option. It is ideal for snorkellers, families and anyone on a day trip who wants to see the reserve's fish without a boat.

The main hazard is the ferry, which berths at the jetty several times a day. Keep well clear of the berth and never dive under the jetty while the ferry is approaching.

Maria Island is a national park with no permanent residents apart from rangers, and the Darlington settlement preserves convict-era buildings from 1825 onwards. The marine reserve along the island's northern and western shores has been no-take since 1991 and has been used for long-term studies of how protection affects rock lobster and fish numbers, so reef life inside it is noticeably richer than outside.

Triabunna, on the Tasman Highway 1 hr 15 min (85 km) north-east of Hobart, is the gateway. The Maria Island passenger ferry (Encounter Maria Island) runs several times daily from Triabunna to the Darlington jetty, about 16 km and roughly 30-45 minutes; it carries people and small amounts of luggage but not vehicles, and dive cylinders should be cleared with the operator first. Private boats launch at the Triabunna ramp (best), Saltworks Road ramp, or Orford (shallow bar at the Prosser River mouth - difficult at low tide).

Walk off the ferry at Darlington; the jetty is the dive site. Enter from the beach beside the jetty rather than jumping from the jetty, and stay clear of the ferry berth, checking ferry times before entering. Gear is carried only a few metres from the jetty head.

Snorkel gear is easy to bring on the ferry; scuba cylinders must be arranged with the ferry operator.

Maria Island's western and northern shores (Darlington, Fossil Cliffs, Painted Cliffs) are sheltered from easterly ocean swell but exposed to strong westerlies and north-westerlies blowing across Mercury Passage, which are common in winter and spring. The eastern side (Mistaken Cape, Bunker Bay) faces the open Tasman Sea and needs westerly weather and small swell. Southerly swell wraps around Cape Peron and the southern end.

Visibility drops after rain as runoff flows from the Prosser River into Mercury Passage. The jetty is sheltered from easterly and southerly swell but exposed to northerly and north-westerly winds across Mercury Passage. Best on calm mornings; dusk dives are rewarding for cuttlefish and squid.

Enter from the beach, swim out along the jetty piles to the end and back, then explore the small kelp garden alongside. Avoid the ferry berth and surface next to the piles. Turn at a third of gas to allow for the swim back and a possibly harder exit, finish with a 3-minute safety stop at about 5 m if the depth allows, and exit where you entered unless an alternative exit has been checked beforehand.

No operator based on Maria Island. Hobart shops run occasional trips: Go Dive Tasmania has offered Ile des Phoques seal dives and filmed Troy D dives; Tasmanian Scuba Diving Club and Tas Uni Dive Club run club trips from Triabunna. Most diving is from private boats.