BOATING NEAR PHANTOM SHIP, Crater Lake National Park. A few thousand years ago a mighty volcano blew its top, collapsed, and formed a great crater. In it now is a 2,000-foot-deep lake of unbelievable blue. This picturesque mass of volcanic rock protruding above the lake, with its resemblance to a full-rigged ship, is well-named. Park naturalists accompany visitors on scheduled launch trips around the lake, interpreting the scenery and the forces of nature that produced it. (Courtesy, Oregon State Highway Commission.)