In Skagway, the WP&YR train ride is the most popular excursion. Note that, besides Juneau, Skagway is the only other port you can helicopter flight-see and dog-sled... same ice-field between the 2 cities, so if you're after that excursion, you have 2 options.
The ziplines (1 in Ketchikan, 2 in Juneau and 1 in ISP/Hoonah) all get great reviews. The Hoonah zipline is billed as the longest and fastest in N. America... They weren't running the last time I was over there - day off for the ships.
Hoohah (ISP) is also one of the better ports for halibut fishing (also, the only place I'd bother with a 1/2 day halibut charter)... There's a decent bear-viewing excursion in Hoonah... if the bears aren't out at the salmon streams, they'll likely be found at the garbage dump!
@Majestic Gems: ISP has been running for over 5 seasons now... hardly "new" by Alaska tourism standards. You should get over there for lunch and check things out sometime... it's only a 15-20 minute flight or an hour's boat ride from Juneau!
Happy Alaska Travels all!
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