Duxbury Harbor is located at the northwestern end of Cape Cod Bay in Duxbury, about 20 miles northwest of the Cape Cod Canal. It is an active recreational boating center.
Initial work in Duxbury Harbor, completed in 1908, involved the construction of a six-foot-deep channel extending from the southwestern end of Duxbury Bay to the Duxbury wharves, and groins at Duxbury Beach (the sandy arm that encloses the east side of Duxbury Bay). The present project, completed in 1960, consists of an anchorage eight feet deep and 21 acres in area in the vicinity of the Duxbury town wharf, and a one-mile-long channel extending from the west side of Duxbury Bay to the eight-foot-deep anchorage, roughly along the same alignment as the 1908 channel. The present channel is eight feet deep and 100 feet wide.