Islander Phil Flash points to an old photograph of The Mercer ferry, one of four ferries that used to frequent the Roanoke Ferry Landing before the I-90 bridge was built. The ferries and a brief history of Roanoke Landing, located on the northern tip of Mercer Island, are featured on a new historical marker at the site. Flash and the sign’s designer, Jim Engelhardt, installed the placard on Tuesday, Jan. 12.