Lighthouse (LtHo)

A fixed structure carrying a navigational light intended to assist mariners by marking a position, route or hazard.

A lighthouse may stand on land, a rock, an offshore foundation or another fixed site and need not be tall or cylindrical. Its light is identified by position, colour, rhythm, period, sectors, elevation and nominal range, often with daymarks, fog signals, racons or other aids nearby. It is an aid to navigation rather than a guarantee of position or safe water. The current chart and light list should be used because characteristics, sectors, obscuration and status can change, while atmospheric visibility limits the distance at which the light can actually be seen.