The Harbor Concert Series returns Sunday, September 15, featuring Royal Hammer (shown), with an opening set from the legendary sax player Glen DaCosta, who has been a member of The Wailers for 45 years and played with Bob Marley for most of the ’70s. Arrive at 4 p.m. with chairs and towels for the lawn; live music will start at 5 p.m. and run to around 8 p.m. Admission is by donation and will support groups that help Rockport and Knox County, with donation buckets on arrival and circulating through the crowds periodically.

Food and beverages, including craft beer and wine, will be available for purchase from Flatbread Co., with some North Haven oysters in the half-shell as well, until they’re gone.

Parking will be available at the former school site at the intersection of Routes 1 and 90, a five-minute walk down to the harbor.

Glen DaCosta worked with Bob Marley long before he became a superstar, beginning back in early 1972 at Lee “Scratch” Perry’s Blackheart Studio in Kingston, Jamaica, where Bob was passing through with Bunny Wailer and Peter Tosh. At the time, DaCosta was a regular studio musician. That was the start of a decade during which DaCosta spent much time with Marley.

Royal Hammer, a five-piece roots reggae collective from Portland, has paid homage for many years to the traditions of Gregory Isaacs, Dennis Brown, Roots Radics and others.