Cook Islands

📍 Aitutaki, southern Cook Islands

The classic: a vast, shallow, near-enclosed lagoon ringed by low motu on the outer reef, with coral heads scattered through brilliant sand shallows. Boat stops are usually over coral with reef fish, giant clams and the occasional ray, and the water is warm and calm enough to stay in for hours.

It is a very big lagoon with genuinely shallow coral in places and real boat traffic on the popular routes: go with a licensed local operator, do not stand on coral, and ask before taking clams or shells — the lagoon is the island's food and its livelihood. Access and any fees are set locally; verify current arrangements.

📍 Aitutaki's lagoon, south-east rim

The best-known island in the lagoon: a small, flat motu on the reef rim with clear sand shallows and shallow coral around it, and a short walk to the outer edge where the lagoon meets the reef. Day boats anchor off it, and the coral around these motu is where much of the lagoon's snorkeling actually happens.

Popular and tidal: at low water some flats are barely awash, so watch the tide and your fins. These are inhabited and customary islands rather than resorts — respect local rules, and take everything back with you.

📍 South-east coast of Rarotonga

Rarotonga's postcard lagoon: a wide, shallow, protected stretch of sand, coral and four small motu inside the reef, easy to walk into from the beach and gentle enough for children in the right conditions, with reef fish, small rays and the occasional turtle.

Honest caveat: the coral close to shore and around the busiest parts of this lagoon has been heavily affected, and its best water is further out towards the motu and the reef edge. Ask locally where it is healthiest right now, and mind the boat channels.

📍 The breaks in Rarotonga's fringing reef

The few openings in the reef around Rarotonga — Rutaki and Aroa among them — are the deepest, clearest and most marine-rich water on the island, where the ocean flows in and out of the lagoon. Turtles, eagle rays and fish concentrate around them, and snorkeling the edge of a pass is a very different experience from the lagoon.

Real safety note: a pass is a current, and an outgoing tide pushes water out through it. Only snorkel a pass with a local guide, on the right tide, staying where the operator puts you — this is not self-guided water. Ask about the day's conditions before you commit.

📍 Aroa and Black Rock, west coast of Rarotonga

The island's easiest saltwater swimming and snorkeling side: sheltered, walk-in shallows over coral and sand on the west coast, with the island's best from-the-beach snorkeling when the wind allows and a community protection arrangement covering part of the coast.

Part of this coast sits under a traditional ra'ui — a community no-take arrangement — and the rules that come with it are local and enforced by the community rather than by a park office. Check current rules before you take or touch anything, and watch the water level at low tide.

The Cook Islands' own dish and the one to order first: raw fish — usually tuna or mahi-mahi — cured briefly in lime, then dressed in coconut cream with onion, tomato, cucumber and chilli. It is cooling, sharp and exactly what you want after a morning in the lagoon.

Tip: Every cook makes it differently, so order it more than once; the version with a lot of lime is the one that tastes best in the heat. Pair it with taro or cassava chips rather than bread.

The umu is an earth oven of hot stones, and a proper island feast from it means pork, chicken and fish with taro, kumara, breadfruit and palusami. Several Rarotongan venues run a Sunday lunch or an island night with drumming and dance, and it is the island's food and its hospitality at once.

Tip: Sunday is widely observed in the Cook Islands — many shops and restaurants shut, and it is worth planning around and respecting. Book a feast in advance rather than turning up.

Most full-day lagoon boat trips include a barbecue lunch on one of the motu: grilled fish, chicken, salad made with what the boat brought, and fruit — eaten on a sandbank with the lagoon all around you. It is the single most memorable meal of a Cook Islands trip.

Tip: Confirm whether lunch is included when you book the trip, take your own water, and carry everything back off the island — these motu are small, customary places with no waste collection.