Knotts Island is a marshy island and a small unincorporated community. The island is shared by Currituck County, North Carolina and Virginia Beach, Virginia, United States, bounded by the Currituck Sound, North Landing River, Back Bay, and Knotts Island Bay. Knotts Island is home to Mackay Island National Wildlife Refuge. Knotts Island is accessible o…Knotts Island is a marshy island and a small unincorporated community. The island is shared by Currituck County, North Carolina and Virginia Beach, Virginia, United States, bounded by the Currituck Sound, North Landing River, Back Bay, and Knotts Island Bay. Knotts Island is home to Mackay Island National Wildlife Refuge. Knotts Island is accessible overland from Virginia Beach using Princess Anne Road, or by water from the Currituck County mainland; the North Carolina Department of Transportation operates a free ferry between Knotts Island and Currituck on the mainland. The ZIP Code for Knotts Island is 27950.