The term 'CAROLINA's Pee Dee River' refers to a river in the U.S. state of South CAROLINA. It is a tributary of the Waccamaw River, which flows into the Atlantic Ocean. The Pee Dee River is approximately 310 miles long and is the longest river in South CAROLINA. It is named after the Pee Dee Native American tribe, who lived in the area before European settlers arrived. The river is an important source of water for many communities in the region, and is also used for recreational activities such as fishing and boating.