The stretch between Gantheaume Point, with its red pindan cliffs and dinosaur footprints, and Riddell Point is described by the Marine Life Network as a popular snorkelling spot on patchy limestone reef around 10 m, with small reef fish, soft corals, sponges and anemones. Sea snakes are common.

It is the most accessible reef dive in Broome, but tides govern everything: plan for a neap high slack.

Diving around Broome: the town's waters are better known for pearling than recreational diving, and the Marine Life Network documents a handful of reef and rock sites off Gantheaume Point and Riddell Point and further offshore that local divers visit on neap tides. The limestone reefs are coated in soft corals, sponges and gorgonians rather than the hard coral of Ningaloo, and fish life is often dense because the sites are rarely dived. The ruling factors are tide and visibility: the same site can be clear on a neap slack and unusable on a spring tide. Saltwater crocodiles, large sharks and seasonal box jellyfish mean divers should plan conservatively, carry surface support and dive with someone who knows the area.

Planning notes: Open Water certification is recommended and the site is rated intermediate. Expect to spend most of the dive around 6 m, with a maximum of about 10 m. It can be reached from shore or by boat depending on conditions. Currents are significant, so timing around the tide is part of the plan. Best season: May–September on neap tides. Traffic: rarely dived (private boat/club only).

Broome is 2,200 km north of Perth with daily flights. Boats launch at the Town Beach ramp on Roebuck Bay (usable only on the higher part of the tide) or the Entrance Point ramp near Gantheaume Point on the ocean side, which is usable at most tides. There is no scheduled day-dive operator in Broome at the time of writing; diving is by private boat, with local knowledge, or through charter vessels.

Offshore rocks and reefs off Gantheaume and Riddell Points are 10–40 minutes from Entrance Point.

Broome has one of the largest tidal ranges in Australia — spring tides approach 10 m in Roebuck Bay — so currents are powerful and visibility depends on the tide. Dive only on neap tides and at slack water; spring tides produce strong currents and turbid water. The dry season (May–October) brings settled weather but strong easterly winds some days; the wet season (November–April) brings cyclones, storms and river run-off.

Box jellyfish and Irukandji occur mainly October–May. Saltwater crocodiles and large sharks inhabit Roebuck Bay and Kimberley waters. Water 23–24 °C in winter to 30 °C+ in summer.

On a neap slack, dive or snorkel the patchy limestone reef at 5–10 m, looking under ledges for small reef fish and invertebrates; watch for sea snakes.

No regular dive operator – private boats with local knowledge only.