I would agree with the train ride. Take in the morning on arrival.
Then after lunch you can go for stroll thru Skagway and walk/hike over to the cemetery . In Skagway there are number of short hikes you can take .
In Juneau the Mendenhall Glacier is not to be missed . Use one of the local shuttles to go to the Glacier . There also a number of hikes around the glacier.
Ketchikan just walk around town , don't miss Still Creek .
__________________
Ships Sailed:
SS Ithaca , Volendam , Mariner of the Seas (x2) , Veendam , Coral Princess , Island Princess (x3) , Emerald ,Sapphire (x3)