Meet the site
Manly Bommie is the outer extension of the Shelly Beach reef system, a stand-alone block of sandstone that Diveplanit describes as a 'shallow, squat bommie 50 m offshore' with a rectangular plateau of rock on top. It sits just outside the sheltered water of Cabbage Tree Bay on the ocean face of the Shelly headland, still inside the aquatic reserve boundary, and it rewards divers who have done the beach dive many times and want the reserve's more dramatic side. The plateau is 6–8 m deep and carpeted with kelp; its edges fall as short walls and stacked ledges to a sand floor at 12–14 m, and the shaded faces carry the sponges, sea tulips and bryozoans that the inner bay largely lacks. Because it is exposed to open-ocean water, fish life here is bigger and denser than on the beach: schools of yellowtail and sweep over the top, kingfish passing in summer, blue groper, red morwong and old wives under the ledges, and wobbegongs, Port Jackson sharks in winter and the occasional eastern blue devilfish in the undercuts. Weedy sea dragons, which have largely disappeared from the inner bay since the March 2022 swells, are still occasionally found in the kelp around the bommie. Giant cuttlefish and octopus use the cracks. The difficulty is entirely logistical. From shore it is a long surface swim over shallow reef and around a headland that breaks in any swell, and the exit is back at Shelly Beach; from a boat it is a five-minute drop from Manly Cove and the easiest dive of the day. Vizzbud's description of an offshore pinnacle to 28 m appears to refer to a different feature and should be disregarded. The bommie suits confident Open Water divers with a guide or local knowledge, and it is a good option when North Head is too rough for the outer sites but the bay is calm.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Manly Bommie is recorded as Pinnacle/Bommie in Sydney Northern Beaches. 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.
- Other water users
- Ask about vessel activity, exclusion areas and the agreed surface arrangements.
- Water movement
- Ask how swell and local exposure affect the proposed entry, exit and route.
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 Manly Bommie suitable for my certification?
The record lists 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 Manly Bommie 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
Wobbegongs, Port Jackson sharks, blue groper, eastern blue devilfish, weedy sea dragons (occasional), kingfish, yellowtail, silver sweep, red morwong, old wives, giant cuttlefish, octopus, sponges, sea tulips
Location
Squat, flat-topped rock bommie about 50 m off the Shelly Beach headland on the ocean side of Cabbage Tree Bay Aquatic Reserve, with a rectangular plateau, kelp on top and sponge-lined walls dropping to sand at around 12–14 m.
Facilities nearby
Shelly Beach: paid car park, toilets, showers, kiosk/Boathouse cafe; air fills at Dive Centre Manly (Belgrave Street) and Pro Dive Manly (Brookvale).
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
diveplanit.comvizzbud.comviz.net.auRecord updated 26 Sept 2026. Source claims are being reviewed.