Day beacon

A day beacon is an unlighted nautical sea mark. Typically, day beacons mark channels whose key points are marked by lighted buoys. Day beacons may also mark smaller navigable routes in their entirety. They are the most common aid to nautical navigation in shallow water as they are relatively inexpensive to install and maintain. Navigation around day beacons is the same as with all other navigational aids.

Identification

Lateral marking

For historical reasons, there are two systems for lateral daybeacons. When proceeding from open water towards harbor, marks with cylindrical topmarks or square dayboards are kept to port in both regions, but colors and numbers are reversed.

When lateral beacons are paired, vessels should pass between the pairing. However, beacons are also frequently placed individually. Generally, single lateral beacons are at the inside corner of a turn. Interior or exterior placement can be determined based upon the passing side (port or starboard) dictated by beacon designation. However, a current chart should always be consulted for all but the shallowest-draft vessels, as channel conditions are rarely ideal.