Sure, Katmai National Park & Preserve encompasses four million acres of rippling coastline, volcanic landscapes and mountain-fringed lakes, but the brown bears are the real draw. A population of around 2200 brown bears (that's more than the human population of the entire Alaska Peninsula) live out their days in the park largely undisturbed. Popular spots like Brooks Falls are the surest place to spot them, but the backcountry is prime territory for wild encounters.
The park is also the location of the Valley of Ten Thousand Smokes, the site of a 1912 volcanic eruption, which is now replete with extinct fumaroles (steam or gas vents in the earth), barren lava flows and narrow gorges.