The Blue Safari Submarine

A driver-guide collects you from the hotel, and the first stop is less nautical than you might expect: the Blue Safari desk, where names are checked and the next group gathers. Then a speedboat runs you out to the submarine’s base on the water. The submarine itself is smaller and lower than the word suggests, mostly hull, with a hatch on top.

On the base the crew give a safety briefing: how the dive runs, how long you are down, and what to do if anyone feels unwell. Then you climb down through the hatch into the cabin. It is air-conditioned and quiet, and the portholes are the whole of the interior design.

The descent is slow, and it is the part people talk about afterwards. Water takes out red light first, then orange, then yellow, so as you go down the colours drain from the world in order and the reef turns green, then blue. Nothing is wrong with your eyes. It is simply what the sea does, and watching it happen through a porthole beats any explanation of it.

Along the bottom the submarine moves slowly, far deeper than any snorkeller goes. Fish come to the glass and leave as they please: shoals that turn all at once, something larger holding still under a ledge, perhaps a moray in a crack in the rock. None of it runs to a schedule, and none of it is promised.

Then you come back up into daylight. On the surface there is a drink and a certificate to prove you went, which children keep and adults pretend not to, and the speedboat takes you back to shore. The time at the water is a couple of hours, and you are back at the hotel with most of the day left.

This is one of two ways to see the reef in Mauritius without learning to dive. The other is the undersea walk, and the honest difference between them is the water. On the walk you are in it, in a helmet, a few metres down in the lagoon. Here you are dry, seated and much deeper, with glass in between. Families split between swimmers and non-swimmers sometimes do one each, and a catamaran day fits into the same week.

Good to know

• The operator sets a minimum age and the medical conditions it excludes. Tell us early about heart trouble, pregnancy or a dislike of small spaces, and we confirm the rules in writing.
• The sea decides. If it is too rough for the speedboat or too murky to see much, the session moves, so book it early in the stay.
• Photographs work through the glass: flash off, and the lens close to the porthole to cut the reflections.
• Ordinary clothes are fine, with a light layer for the air-conditioning. Nothing gets wet except, sometimes, you on the speedboat.
• Lunch is not included. A morning session leaves the afternoon for the beach.