Juneau and Ketchikan both have dock-fishing available in designated areas... I don't know what rod rental will cost - I would guess something in the $8 to $15 range for the day. A one-day non-resident fishing license will cost you $20, plus another $10 if you want to fish for King Salmon. In Juneau, you'll need to take a taxi to the DIPAC Fish Hatchery. The rental stand is just a few yards from the entrance to the hatchery, and you'll be fishing from the DIPAC dock. In Ketchikan, just ask around on Creek Street, and don't forget to look down while you're walking the street...
The big variable will be when you're here. Right now, there's not much dock fishing available at the rental shack because it's just King Salmon running now. In July and August you'll see thousands of Pink and Keta salmon running in every creek, river and stream near all the ports, and that's when the rental shacks are usually open and available. Be sure to know the difference between a salmon you can eat and one that's "spawned out" or "dark"... once they hit the fresh water, many of the fish will be "necrotic"... rotten... and not something you'd want to keep to eat. They're still fun to catch when they're dark and inedible, just be sure to handle them kindly as they should be released to live out their last few days.
(That actually raises yet another question... what do you intend to do with the fish you catch? If you're fishing for food to take home, you'll be on your own as far as getting the fish in a bag and delivered to a fish processor who can fillet, smoke, freeze, vac-pac, etc. your catch and have it shipped home. If you're just fishing for fun, catch and release all you like... it's a blast!)
Happy Alaska Travels!
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