For six months, the blue lagoon was a flash of luminous teal through the trees as I sped by. On Monday, I finally slowed down, passed through the curtain of trees, and slipped into its cool clear depths. The water is so pure, so transparent, that you can see the tiny delicate anemones waving in the shallows, but so deep that beyond your own floating limbs there’s nothing but intense layers of colour. It is as warm as the turquoise sea it flows into, womblike, protective, peaceful. I've been back every morning since.