The six-mile long Alaskan glacier on the Kenai Peninsula is within the Chugach National Forest near Portage Lake. Portage Glacier was at one time a large 14-mile long glacier covering the Portage Valley. Surveyor Thomas Mendenhall named it in 1898 because it was on the portage route from Prince William Sound to Turnagain Arm. The glacier must be viewed by boat and has a visitor center.