Hi Al Maritime center is a kind name for the Quincy police maritime unit building and public boat ramp on Bay View Road adjacent to the Quincy yacht club 137 Bayview Road Quincy, MA 02169 . there is a concrete ramp, about 8 parking spaces next to it and a large paved lot 20 yards away with plenty of room to include boat trailers. I checked with the police unit and the large lot has no resident restrictions and is open for overnight parking. A good place if you are camping on the Islands. It sometimes has a working outdoor shower. there is a concrete ramp but a small gravelly/sand area to the left side if you prefer to launch from that surface. It's busy on summer weekends but not impossible. Occasionally in the summer weekends a lobster boat will tie up at the adjacent dock and sell live lobsters Regards Pablo