Rock Island is an island in Narragansett Bay in the U.S. state of Rhode Island.Rock Island is a small rocky island near Pawtuxet Village and is now connected to the mainland by a causeway.The island is part of the Salter Grove public picnic ground and is the site for a proposed man-made salt marsh using dredged materials.The island contains several unusual fossils.This Rhode Island state location article is a stub.