On the Net I discovered the Alaska Pass which gives you for a certain number of days unlimited use of all transportation in Alaska and the Yukon. We bought the eight-day pass to be used over 12 days.
Longer passes are even a better buy.
Leaving from Bellingham, Washington on the ferry we went up the inside passage stopping at Ketchikan, Wrangell, Juneau and leaving at Skagway. We spent three nights on the ferry with a cabin. Cafeteria served tasty food a very reasonable price. Two forest rangers gave interesting lectures through out the day. The crew was great and we meet so many nice people of all ages.