The Easter Group is the central cluster of the Houtman Abrolhos. Eco Abrolhos describes Little Sandy Island as its primary mooring, with a channel ideal for snorkelling where plate corals line the reef edge in excellent condition and the largest colony of sea lions in the Abrolhos – around 13 individuals – is found. Wooded Island nearby is a birdwatchers' paradise hosting the lesser noddy, found in only two places in the world. Rat Island is the group's main rock lobster fishing-camp island.

The Easter Group is also home to Anemone Lump and Rolland Passage (separate rows), making it the core of most liveaboard itineraries.

The Houtman Abrolhos lie 60-80 km west of Geraldton (about 420 km north of Perth). There is no public accommodation or camping on the islands, so divers visit on liveaboard trips departing Geraldton (a 3-5 hour crossing), on private vessels using the public moorings, or – for snorkelling only – on scenic-flight day tours that land on East Wallabi Island. The Easter Group is about 60 km (3-4 hours) west of Geraldton.

Eco Abrolhos uses Little Sandy Island as its primary mooring, with a channel for snorkelling and glass-bottom tours. Private boats use the public moorings.

The Abrolhos sit on the edge of the continental shelf in the path of the warm Leeuwin Current, which keeps water at 20-24°C and supports the world's southernmost major coral reefs. The islands are exposed to the south-west swell and to strong southerly winds that blow most afternoons from October to March; the crossing from Geraldton is often rough. Marine Life Network recommends March-May and September-November; late summer-autumn highs give the calmest seas.

Western rock lobster season (15 March-30 June) brings fishing camps and boat traffic. The channel at Little Sandy Island is sheltered and used as a liveaboard mooring.

Snorkel or dive along the channel edge at Little Sandy Island over the plate corals, keeping a respectful distance from the sea lions and letting them approach.

Liveaboard only for diving: Image Dive – 'Southern Image', the only dedicated dive boat at the Abrolhos (4 days/4 nights from Geraldton, max 8 divers, 3-4 dives a day); Eco Abrolhos Cruises – 5-day small-group cruises from Geraldton with snorkelling and diving; occasional Perth club charters. Batavia Coast Dive & Watersports (Geraldton) runs Abrolhos trips when boats are available.