Dive Site: Agincourt Reef

About Agincourt Reef

Agincourt Reef sits on the outer edge of the Great Barrier Reef, roughly 60–72 km off Port Douglas in Far North Queensland, at the southern end of the true ribbon reefs that run parallel to the continental shelf drop-off. Rather than one continuous wall, it is a cluster of long, narrow reef systems and isolated coral bommies, commonly numbered Agincourt 1 through 4 or 5, giving operators several distinct dive and snorkel sites to rotate between depending on conditions.\n\nBecause it lies on the shelf edge facing open ocean, Agincourt benefits from exceptionally clear water compared with reefs closer to the mainland, together with sweeping plate and table corals, walls and coral gardens. Large plate corals provide shelter for coral trout and other grouper species, while giant clams are visible in the shallows and are sometimes exposed at low tide.\n\nAccess is boat-only, typically via full-day catamaran trips from Port Douglas that anchor at a floating pontoon for snorkelling, introductory and certified diving, and semi-submersible or glass-bottom viewing. Researchers have documented a resident green sea turtle population, including a turtle nursery beneath one operator pontoon. The area is also recognised as an Important Shark and Ray Area, reflecting its complex outer-reef habitat.

Dive site facts: Agincourt Reef

Depth

2–20 m

Typical dive

Multi-level reef and coral-garden dive

Current

Variable with weather and site selection

Visibility

Commonly 15–30 m

Water temperature

About 24–29°C seasonally

Entry

Boat and floating pontoon

Level

Beginner to intermediate

Dive type

Outer ribbon reef, coral garden and wall

Region / port

Great Barrier Reef, Australia

Coordinates

16.0300° S, 145.8190° E

Conditions & Currents

Agincourt Reef is reached by boat from Port Douglas, with most full-day trips taking roughly 90 minutes to two hours each way. Operators use floating activity pontoons for snorkelling, introductory scuba and certified diving. Because the reef sits on the open continental shelf edge, sea state, visibility and local water movement can change with weather; divers should follow the operator briefing and use the site selected for that day’s conditions.

Marine life & sighting chances

Green sea turtle

Year-round · common

Coral trout

Year-round · common

Giant clam

Year-round · common

Butterflyfish

Year-round · common

Wrasse

Year-round · common

Damselfish

Year-round · common

Reef shark

Year-round · occasional

Ray

Year-round · occasional

Dive profile & how the dive runs

Most dives follow a multi-level profile from shallow coral-garden tops around 2 m to a typical maximum near 16–20 m. Depending on the chosen Agincourt section, divers explore isolated bommies, broad plate-coral formations and short wall sections. Pontoon operations can separate introductory divers, snorkellers and certified groups, while the operator selects the day’s mooring for conditions.

Underwater photography

Large plate and table corals, clear blue water and green turtles suit wide-angle photography. Coral trout sheltering below plates, giant clams and occasional nudibranchs provide closer subjects. Good buoyancy is essential around fragile coral structures.

Combine with nearby dive sites

• Agincourt Reef No. 1

  A numbered section within the same outer-ribbon reef complex

• Agincourt Reef No. 2

  A nearby operator site selected according to conditions

• Agincourt Reef No. 3

  Outer-reef habitat recognised as an Important Shark and Ray Area

Getting there & logistics

Agincourt Reef is accessible only by boat. Full-day departures normally leave Port Douglas in the morning and take about 90 minutes to two hours each way. Many trips operate from a floating pontoon with equipment, guided dives, snorkelling and semi-submersible or glass-bottom viewing.

Safety & environment

This is an exposed outer-reef location where wind, sea state, visibility and local water movement can change. Follow the operator’s briefing, stay within the assigned group and depth limits, maintain careful buoyancy over coral and confirm current conditions before entering the water.

Who it suits — and who it doesn't

FAQ

Agincourt Reef FAQ

Liveaboards diving Agincourt Reef

These liveaboards may visit Agincourt Reef on selected itineraries — the exact dive sites depend on departure, weather and conditions.

Spoilsport

Australia

28 guests30 m

$291/day

Odyssey Liveaboard

Australia

20 guests24 m

$392/day