Aiken State Park had some self-described "river rats" among its visitors June 17, playing host to the fourth annual Blackwater Summer Festival, with a focus on the health, protection and enjoyment of the Edisto River. Friends of the Edisto River, the sponsoring organization, had a variety of displays on hand, encouraging visitors to learn more about the Edisto and get involved with efforts to protect  one of the longest free-flowing blackwater rivers in America.