By Hilary Nangle, Globe correspondent
Visit and climb the towers of seven Mid-coast lighthouses during the Midcoast Maine Lighthouse Challenge (207-594-4174, www.lighthousefoundation.org), June 29-30. Register for the challenge at any of the lighthouses. There’s no cost to participate, but some lighthouses have admission or parking fees. Participating lights are Dyce Head, Castine; Fort Point, Stockton Springs; Grindle Point, Islesboro; Rockland Breakwater, Rockland; Owls Head, Owls Head; Marshall Point, Port Clyde; and Pemaquid Point, Bristol. Two special activities complement the challenge. A 4.5-hour Lighthouse Sunset Cruiseaboard The P/V Elizabeth Ann departs Port Clyde on Friday, June 28, at 4:30 p.m., ($40). A Saturday evening program blending stories and songis slated at the Owls Head Community Center, Sat. June 29 at 7 p.m.(suggested donation, $5).