The entrance to the channel was marked by Ambrose Light which doubled as a staging area for pilot boats, most notably the Sandy Hook Pilots. Prior to the construction of the light tower in 1967 the channel was marked by the Ambrose Lightship, one of a class of lightships operated and maintained by the United States Coast Guard for the express purpose of marking main shipping channels for major ports. After being struck by small boats on a number of occasions, the light tower was redesigned and relocated in 1999, and finally decommissioned and removed in 2008.