Abstract: The marine Vessel Traffic System (VTS) is an improved radar harbor surveillance sensor, computer and display system that monitors marine harbor traffic, provides advisories to vessels in areas selected by the system operators, and provide the operators of the system with an early warning of unacceptable traffic conflicts in the confined waterways of the harbor. The VTS collects harbor traffic information from multiple remote sensor collection sites around the harbor and integrates, records, merges and presents the remote site data onto a single operator display, selected from a plurality of operator displays. VTS provides quick accurate computer generated graphic display of the harbor traffic, possible surface and subsurface conflicts, and key vessel identification information and the VTS documents incidents and traffic conditions for the Coast Guard or other waterway authorities.