The littoral zone is the part of the ocean closest to the shore. The littoral zone is from the shoreline to 600 feet (183 meters) out into the water and is divided into three zones: the supralittoral zone, the intertidal zone and the sublittoral zone.

The supralittoral, or spray, zone is only underwater during unusually high tides or during storms. It starts at the high-tide line and goes toward dry land. The intertidal zone is between the high-tide and low-tide lines. The sublittoral zone extends from the low-tide line out to 200 meters.

The littoral zone is a tricky area for predicting water conditions because so many factors affect it. Coastal currents, onshore and offshore winds, reefs, bays and the shape of the shoreline are some of the things sailors have to deal with in this zone.

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