Undersea Walk

The boat takes a few minutes to get from the jetty at Grand Baie to the platform, which is moored in the lagoon and runs on solar power. That is long enough for the briefing: two hand signals, how to clear your ears, and what happens if you want to come up. Then you sit on the ladder and go down it backwards until the water is at your chin.

The helmet is lowered onto your shoulders while you are still on the ladder. It is heavy in the air and weightless the moment you are under, and air is pumped down to it from the boat above, so you breathe normally the entire time: no regulator, nothing in your mouth. Your hair stays dry. If you wear glasses, they stay on.

Then you walk. The floor is sand and broken coral, the light comes down in bands, and the fish arrive within a minute because they have learned that people at this platform mean food. A shoal of sergeant majors comes to look at you. A guide walks with you the whole way, holding your elbow if you want it, pointing at the things you would otherwise miss: a wrasse, an urchin, whatever is sitting under the ledge.

It is a strange and completely undramatic thing to do. There is no skill to acquire, no course, no certificate, and nobody has to be brave. Children who will not put their face in the water do this happily. Grandparents do it. It is often the excursion a family books together when half of them dive and half of them do not, and it is the honest alternative to scuba rather than a lesser version of it.

The other way to see the reef without diving is the Blue Safari submarine, which goes much deeper and keeps you dry behind glass. The walk is the one that puts you in the water with the fish.

You are back on the boat before you are cold, and then Grand Baie is yours for an hour or two, for lunch on the front, a swim or the shops, before the driver takes you back to the hotel. It pairs easily with a lagoon morning or a catamaran day later in the week.

Good to know

• Slot lengths, prices and minimum ages are set by the operator and vary between them. We confirm yours in writing before you book.
• It is weather-dependent. A stirred-up lagoon means poor visibility, and a good operator moves you rather than sending you down into cloud.
• Tell us about ear or sinus trouble, heart or respiratory conditions and pregnancy. Operators exclude some of these, and it is better known now than at the jetty.
• Take a waterproof camera if you have one, or ask whether the guide shoots photographs. Yours will not survive the descent in a pocket.
• Book it for a morning early in the stay. If the sea is wrong that day there is somewhere to move it to.
• Bring a towel, sun cream and a change of clothes. You come up wet from the neck down, and there is Grand Baie to see afterwards.