The White Sandbank

Mayotte's lagoon - among the world's largest and deepest, ringed by a double barrier - keeps a signature trick: the ilot de sable blanc, a bare bank of white coral sand that surfaces with the tide in the middle of the turquoise, no palm, no rock, no anything except sand, water and horizon. Boat trips time the tides to land picnics on the bank, snorkel stops en route work the coral heads and turtle seagrass, and dolphins - the lagoon holds resident pods - frequently write themselves into the crossing. It is the minimalist Indian Ocean postcard, achieved with two ingredients.

What's there

• The bare sandbank - white sand, turquoise ring, nothing else.
• The snorkel stops - coral heads and turtles on the crossing.
• The dolphin pods - residents met mid-lagoon with luck.
• The double barrier - the reef lines drawing the lagoon's edges.

When to go

May to October for dry-season clarity; the bank's size is the tide's decision - operators schedule around the windows. Morning trips get the calmest water and the emptiest sand.

Before you go

There is no shade whatsoever - the sunscreen-hat-water triad is safety equipment; the bank drowns on schedule, so the boat's timetable is not a suggestion. Choose operators with lagoon-respect manners (no anchor-dropping on coral, distance from dolphins). Swimming is dreamlike and current-aware.

Nearby

The lagoon's turtle sites, Grande-Terre's beaches and Mamoudzou.