To many people, southern Oregon means one thing: Crater Lake. It's the deepest lake in the country, and it's arguably the most beautiful. Visitors to the area can't imagine the sudden impact of the awesome grandeur that lies ahead as they approach the rim of the caldera, and that makes the lake's appearance 1,000 feet below all the more stunning.

With Mount Shasta, Mount Lassen, the Trinity Alps, and the Marble Mountains just south of the Oregon-California border, it's hard to get excited about the low peaks of southern Oregon. Evidence of past volcanic activity is less vertical here, but more dramatic. Mount Mazama, in which Crater Lake is located, once stood as tall as its neighbors to the south. Then, 7,700 years ago, it erupted with almost unimaginable violence, a blast estimated at about 100 times greater than that of Mount St. Helens. When it had finished erupting, the volcano collapsed in on itself, forming a vast caldera 6 miles wide and almost 4,000 feet deep. Within 500 years, the caldera filled with water to become today's Crater Lake. The sapphire-blue lake's surface is at the base of 1,000- to 2,000-foot cliffs that rise to a total elevation of more than 8,000 feet.

The lake has no inlet or outlet streams and is fed solely by springs, snowmelt, and rainfall. Evaporation and ground seepage keep the lake at a nearly constant level. Because it is so deep, it rarely freezes over entirely, despite long, cold winters. The high elevation of the caldera rim and heavy winter snowfalls mean that the summer season here is short.

Gold prospectors stumbled upon the lake's rim in 1853. The American Indian tribes of the region, who considered the lake sacred, had never mentioned its existence to explorers and settlers. By 1886, explorers had made soundings and established its depth at 1,996 feet, making it the deepest lake in the United States. Sonar soundings later set the depth at 1,943 feet. In 1902, the lake was designated a national park.

"I came, I saw, I left," could be the motto of many of the almost 500,000 annual visitors. From mid-July to mid-September, they ride dutifully around the Rim Road and then move on. If you're looking to interact with the landscape on a more personal level, you have some options, such as road biking around the Rim Road or day hiking to the summits of several peaks, including that of 760-foot Wizard Island in the middle of the lake. The boat tours are highly recommended, but you first need to make the short but steep hike to Cleetwood Cove, 700 feet below the road and the only place you can get to water's edge. The area also offers superb cross-country skiing and snowshoeing opportunities in winter.

The Pacific Crest Trail passes through the park, with a 6-mile stretch on the west side of the lake. Wildlife is mostly limited to the lowlands surrounding the caldera, although at the summit you can see hawks, eagles, and many types of birds and small mammals. In addition, the spotted owl has been found nesting within the park boundaries. The forested slopes provide refuge for deer, elk, porcupine, coyote, and fox, and trout and salmon live in the lake.