Cockle Cove is a great beach for families and adults. The warm Nantucket Sound water is good for swimming and windsurfing. Parents appreciate the calm waves and long stretches of soft sand. One of many beaches lining Chatham's southern border, Cockle Cove is a fairly sizable beach. It is long and narrow, but offers a lot of room for favorite beach activities. Cockle Cove is also a popular spot with windsurfers and kayakers.