DESCRIZIONE
A floating waterway marker device (100) in the form of a buoy or a waterway navigation mark is provided. Said device comprises a body (10) and an at least one light source (13A, 13B), wherein in the body (10) a number of periodically spaced recesses (11) are circumferentially arranged to a predetermined depth. The waterway marker device (100) further comprises a number of optical fibers (4) extending from said at least one light source (13A, 13B) to each of the recesses (11) and configured to convey light emitted by the at least one light source (13A, 13B) such, that exiting light is directed to an ambient around the periphery of the waterway marker device (100).