Crater Lake National Park, Oregon

The setting: Oregon's only national park, Crater Lake is centered on the country's deepest lake, created by the eruption and subsequent collapse of Mount Mazama 7,700 years ago.

The inside scoop: You shouldn't miss hiking down into the caldera on the short but steep Cleetwood Cove trail, but since it's the only route down to the lake and the popular boat tours, it tends to get crowded. Karl Samson, who wrote Frommer's Oregon and has visited Crater Lake more than ten times, suggests supplementing that with the quieter, 2.5-mile trail up Mount Scott. "The views from this summit on the rim of the caldera are stupendous," he says.

Plan B: Board a boat to Wizard Island (pictured), the cone of a new volcano that is sprouting up in the western end of the lake. The island's two hiking trails will take you up the rocky peak, scattered with a few hardy conifers, and past large chunks of cooled lava. Be prepared to spend the day there, however, since you're not guaranteed a ride back to Cleetwood Cove until the last boat of the day (overnight stays aren't allowed).

Money-saving tip: Have dinner on the deck of the Crater Lake Lodge as you watch the sun go down, then head to your less expensive motel unit ($90–$120) at the Prospect Historic Hotel, less than 45 minutes from the rim of the caldera.

When to go: The park is quieter but not yet snowy in September (Wizard Island closes mid-September). If you visit in late July or early August, take the Castle Crest Wildflower Trail "through meadows that are awash with color," says Samson.

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