Abstract: Arrangement for visualizing the movements of marine vessels by television display. The arrangement comprises a position determination unit which is arranged to continuously provide position determinations in the form of coordinate values in a certain coordinate system for a number of vessels together with a data processing equipment which is arranged to feed the coordinate values with predetermined control signals each in the form of a television signal arranged to bring about a stylized image on a television screen of the respective floating units. The control signals are integrated in such a way with the respective coordinate values that a number of images are produced on a television screen of the vessel in positions which correspond to the mutual position between them in the system of coordinates. These images are moved on the television screen in accordance with the change in the continuously output coordinate values.