It’s almost time for that long-awaited family vacation, and you’re starting to make plans. With so many destination choices, how do you decide where to go? For many families, that choice is often one of America’s national parks. The U.S. government maintains hundreds of national parks, monuments, recreation areas, and historic sites that are visited by millions of people each year. These include many of the country’s most spectacular and scenic locations as well as many of its most historic and storied places. Here are seven of the best national parks the United States has to offer. Four of them are listed as UNESCO World Heritage sites.

　　Yellowstone National Park

　　Yellowstone National ParkScenics of America/PhotoLink/Getty ImagesIt is hard not to list this one first—the “mother park,” the country’s and world’s first national park. Occupying the northwest corner of Wyoming and slivers of eastern Idaho and southern Montana, Yellowstone is an enchanting place. The greatest draws are its hydrothermal features—the world’s largest collection of geysers (notably the renowned Old Faithful), colorful hot pools, mud cauldrons, and hot springs and terraces. But the park also features a beautiful lake, which occupies the cauldron of an ancient volcano, and a majestic two-tiered waterfall that is at the western end the spectacular Grand Canyon of the Yellowstone River that features towering multihued rock formations. Herds of bison and elk roam the park, and Yellowstone is famous for its bears—and, since the 1990s, its packs of wolves.

　　Grand Teton National Park

　　Grand Teton National ParkAutumn foliage in early morning sunlight, with the Teton Range in the background, Grand Teton National Park, northwestern Wyoming, U.S.Just a short way south of Yellowstone in Wyoming, the magnificent Teton Range rises up sharply for more than a mile (1.6 km) from a lake-filled valley. It is one of America’s most breathtakingly scenic places and the subject of countless photographs. Sunrise on the range from a tent or from the park’s fine lodge is one of the most beautiful sights a visitor could hope to see. Hiking is popular on the park’s vast network of trails, especially in the narrow, deep valleys between the mountains with waterfalls cascading down the slopes. If you’re lucky, maybe you will get to eat lunch while watching a moose grazing nearby in a stream.

　　Grand Canyon National ParkNothing can quite prepare a person for the awe-inspiring grandeur of one of the most famous places in the world. The Grand Canyon winds for 277 miles (446) km across northwestern Arizona in an intricately carved chasm of imposing peaks, buttes, gorges, and ravines in layers of red, buff and gray, delicate green and pink, brown, slate gray, and purple rock—all formed over millions of years. Great crowds of people from throughout the world come to see this marvel each year. Most visitors peer over the rim from up top to the canyon floor a mile below. The more hardy souls hike or ride donkeys down to the bottom and then must hike back up. The lucky ones experience the floor of the canyon from rafts that float down the Colorado River.

　　Rocky Mountain National Park

　　Rocky Mountain National ParkRocky Mountain National Park, north-central Colorado.Straddling the Continental Divide in north-central Colorado, this park encompasses a spectacular portion of the southern Rocky Mountains. It is home to dozens of peaks over 12,000 feet (3,650 meters) in elevation, capped by Longs Peak at 14,259 feet (4,346 meters). The park’s close proximity to Denver to the southeast makes it one of the country’s most-visited parks, and it is a haven for hikers, climbers, and campers. Many try their luck scaling Longs Peak, one of Colorado’s famed “Fourteener” mountains. Most, however, try climbing lower peaks or stay on the park’s hundreds of miles of trails. A highly popular activity is driving up Trail Ridge Road, which crosses the divide above 12,000 feet and affords panoramic vistas.

　　Mount Rainier National Park

　　Mount RainierMount Rainier, Mount Rainier National Park, Washington.(more)R. Morley—PhotoLink/Getty ImagesAnyone in Seattle, Washington, who looks southeast on a clear day, will catch sight of the gigantic, looming Mount Rainier, a dormant glacier-covered volcano. Such viewings are fairly rare, though, as the mountain is frequently shrouded in clouds. It also receives large amounts of precipitation, most notably snow; the park has recorded some of the world’s highest annual snowfall accumulations. All that moisture produces lush vegetation that includes towering conifers and fantastic displays of wildflowers in spring and summer. Mount Rainier is a mountaineering mecca, with thousands of climbers ascending to its 14,410-foot (4,392-meter) summit annually.

　　Olympic National Park

　　Olympic National Park: Hoh RainforestTrail in the Hoh Rainforest, Olympic National Park, northwestern Washington, U.S.(more)Glen Allison/Getty ImagesAnother spectacular area close to Seattle is Olympic National Park, an ecologically diverse wonderland occupying much of the Olympic Peninsula in northwestern Washington. It preserves the Olympic Mountains and their magnificent temperate rainforest vegetation, in which a rich array of animal species thrive. Of note is the Hoh River rainforest on the range’s western slope that supports growths of giant Sitka spruce and western hemlock trees and a forest floor thickly carpeted with mosses, lichens, and ferns. Large yellow Pacific banana slugs are often seen there. A small unit of the park on the west coast of the peninsula contains scenic beaches and islets.

　　Mammoth Cave National Park

　　Mammoth Cave National ParkStalactites hanging in Mammoth Cave National Park, west-central Kentucky.Lying underneath a portion of west-central Kentucky is the vast Mammoth Cave. Along with connected caves to the east and west, the entire mapped complex constitutes the largest cave system in the world. The caves were formed by the dissolution of limestone by water, which also produced striking stalactite and stalagmite rock formations. The cave is inhabited by several unique animal species, including cave crickets, eyeless fish, and eyeless crayfish. A highlight of cave tours occurs when the lights are turned out, and visitors are momentarily plunged into total darkness and silence.