Meet the site
Sudbury Reef is a platform reef with a small sand cay lying about 35 km east-south-east of Cairns, south of Fitzroy Island and inshore of the Moore and Briggs reef group. It does not feature on the regular day-trip circuit, and published dive descriptions are scarce, so the account here is based on its geography and on the character of similar mid-shelf reefs nearby. Its value for divers is as a quiet alternative for private charters, sailing groups and private boat owners, who can reach it in a little over an hour from Cairns in fair weather and are unlikely to share it with other boats. A small sand cay, typical of mid-shelf platform reefs, provides a landmark and a lee on the western side, where the reef edge usually slopes gently from a shallow reef flat into sand at 10-18 m. Expect a mid-shelf coral community of branching, plate and massive hard corals with soft corals in sheltered spots, and fish such as parrotfish, wrasse, damselfish, butterflyfish, coral trout, sweetlips and emperors, with turtles, giant clams and reef sharks likely. Visibility is generally lower than on the outer reefs, typically 8-15 m, and falls after rain. Divers visiting independently need to be self-sufficient, check the GBRMPA zoning map (much of the reef system around Cairns is zoned Marine National Park or Conservation Park) and use public moorings or anchor only in sand. Its proximity to Fitzroy Island makes it a possible stop on a sailing itinerary.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Sudbury Reef is recorded as Reef in Cairns. The listed access is boat (day trip). 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.
- Current and timing
- Ask how the operator assesses the current window for the actual route. Historical tide notes are not a departure instruction.
- 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 Sudbury Reef 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 Sudbury Reef 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
Turtles, giant clams, parrotfish, wrasse, damselfish, butterflyfish, coral trout, sweetlips, emperors, reef sharks (expected; no published species list)
Location
Platform reef with a small sand cay about 35 km east-south-east of Cairns, south of Fitzroy Island; used by smaller charter and sailing boats.
Facilities nearby
None; nearest facilities, fills and boat ramps in Cairns
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
reeftrip.comRecord updated 26 Sept 2026. Source claims are being reviewed.