Don't go to Juneau without heading out to Mendenhall Glacier. (We actually rented a car since we have been there so many times. There is now car rental at the cruise ship dock.) Black Bears are almost an assured sight if you stay at the Glacier long enough. Also, the whale watching expedition is the best anywhere. Don't pre-order the Mount Roberts Tramway. If there are low clouds, it is basically a waste; but if you can see, it's well worth it.