Channel of Life: Snorkeling Hol Chan Marine Reserve

You feel the reef before you see it — a sudden coolness underfoot, the water’s surface clarifying until the boat’s shadow becomes a silhouette on the sand below. On a good morning off San Pedro the Caribbean is a liquid sheet of glass; the captain nudges the bow and the guide points with a gnarled finger. There, a break in the reef — Hol Chan, the “little channel” — widens like a doorway into a world that moves on a different clock. Schools of baitfish shimmer like coins; parrotfish chew at the coral with mechanical insistence; a nurse shark, obligingly slow, threads itself into a sandy trough. The canal breathes and you, in a mask and a snorkel, are invited in.