If you're looking for bears, Katmai is the place. Across the Shelikof Strait from Kodiak Island and with a very volcanic and lunar-like landscape, Katmai National Park has smoking craters and salmon choked rivers. The main town in the Katmai environs is King Salmon. This leaves little doubt as to what locals fish for and also accounts for the large brown bear population.
So while it's a pretty safe bet there will be good fishing, it's also safe to assume you'll have to share your catch with Katmai's furry inhabitants. Tours out of King Salmon or nearby Naknek are geared towards bear sighting and McNeil River State Game Sanctuary above northeast Katmai is the remote spot to spot. Permits, patience and a charter plane are crucial.
Katmai is the home to not only large quantities of brown bear but also several volcanoes, most of which are now dormant. Explore the Valley of Ten Thousand Smokes on a tour out of Brooks Camp, and do some hiking through this area that looks something like a cross between the Grand Canyon in miniature and the Moon in spring. The smoke has mostly blown off, but this area has, even in the past 100 years, been altered by eruptions from Mt. Novarupta and volcanoes Mageik, Martin and Trident. There are short hikes through the area, though not many marked trails.
Canoe and kayak rentals are available for long floats through backcountry down the Grosvenor and Savonoski Rivers. Trips with fold-up kayaks can be arranged out of Anchorage.
Katmai National Park is southeast of Anchorage on the Alaska Peninsula and west of Kodiak Island.