Meet the site
Crescent Bay is a spectacular crescent of white sand below the cliffs of Mount Brown, south of Port Arthur, reached on foot by a popular walking track from Remarkable Cave. The Marine Life Network guide describes deep cliffs at 20-25 m with delicate sponges and anemones and small crayfish, reachable by boat or by the foot track. Because the cliffs plunge into relatively deep water, the reef beneath them is below much of the surge that scours the shallower parts of this exposed coast, allowing more delicate invertebrates to grow on the rock faces. Sponges in a range of colours and forms, jewel anemones, hydroids and ascidians cover shaded surfaces, and small rock lobsters hide in the cracks. Fish life includes wrasse, leatherjackets, butterfly perch and morwong, and fur seals patrol this coast. The site is rarely dived; access is either a boat run out of Port Arthur or a long walk that few divers will attempt with cold-water kit. It suits Advanced divers comfortable at 20-25 m with a competent boat cover. The scenery around Crescent Bay and Mount Brown is among the best on the Tasman Peninsula, with sand dunes, dolerite columns and views to Cape Pillar and Tasman Island. Nearby Remarkable Cave, a sea cave that can be viewed from a lookout, is not a dive site – waves surge through it with great force. Treat the published details as indicative and plan on a calm day. A private boat is the realistic option; plan a second, shallower dive inside Port Arthur afterwards to break the return run and off-gas in sheltered water.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Crescent Bay – Mt Brown Cliffs is recorded as Wall in Tasman Peninsula. The listed access is shore or boat. Confirm the actual meeting point, route and permission to visit; a map pin does not establish any of these.
Topics flagged by the stored research
These are questions prompted by the existing notes, not a verified or complete hazard assessment.
- Water movement
- Ask how swell and local exposure affect the proposed entry, exit and route.
- Overhead environments
- Ask whether the plan stays entirely in open water. A wreck or cave listing is not permission or training to enter.
Historical access notes exist for this record, but have not been independently verified for current use. Request current directions from the operator or site manager rather than following an old entry description.
Questions, answered
Is Crescent Bay – Mt Brown Cliffs suitable for my certification?
The record lists Advanced Open Water. That does not establish suitability for every route or day. Share your training, recent experience and equipment needs with the operator and ask about the specific proposed dive.
Can I book Crescent Bay – Mt Brown Cliffs through YouDive?
YouDive is an independent research directory. Contact an operator directly to confirm whether it currently runs the trip, the inclusions and the booking terms.
What you might see
Sponges, jewel anemones, hydroids, ascidians, small rock lobster, wrasse, leatherjackets, butterfly perch, morwong, fur seals
Location
Deep cliff-base reef at Crescent Bay under Mount Brown, south of Port Arthur near Remarkable Cave.
Facilities nearby
Remarkable Cave car park has toilets; fills at Eaglehawk Neck or Hobart.
Before you make plans
Conditions, access and operator schedules can change. This is a location guide, not a dive plan. Ask a local operator about current conditions and suitability for your training and experience.
Sources & further reading
marinelife.org.auRecord updated 26 Sept 2026. Source claims are being reviewed.