Know the park before you reach the gate.

Geysers, hot springs and the densest wildlife viewing in the lower 48.

Granite cliffs, giant sequoias and some of the tallest waterfalls in North America.

A mile-deep gorge cut by the Colorado River, with two very different rims.

Towering sandstone walls, river hikes and a famous chain-assisted summit.

America's most-visited national park: misty ridges, old-growth forest and historic farmsteads.

Alpine tundra, elk herds and the highest continuous paved road in the US.

Granite coastline, carriage roads and the first sunrise view in the US for part of the year.

Jagged peaks, turquoise lakes and the Going-to-the-Sun Road.

Sheer peaks rising straight from the valley floor, with lakes and wildlife below.

More than 2,000 natural stone arches in red desert rock.

Four presidents carved into Black Hills granite, 60 feet tall each.

High-elevation amphitheaters packed with orange hoodoos and very dark night skies

A 100-mile wrinkle in the earth with cliffs, petroglyphs and historic Fruita orchards

Deep canyons carved by the Colorado and Green rivers, split into four wild districts.

Glacier-capped peaks, temperate rain forest and wild Pacific beaches in one park.

A glacier-covered 14,410-foot volcano ringed by wildflower meadows and old-growth forest.

Where the Mojave and Colorado deserts meet, full of Joshua trees and granite boulders

The hottest, driest and lowest national park, with salt flats, dunes and colorful canyons

Home of the General Sherman Tree, the largest tree on Earth by volume.

A glacier-carved canyon over a mile deep, plus the giant General Grant Tree.

The deepest lake in the US, filling the collapsed caldera of an ancient volcano.

A long, forested ridge in the Blue Ridge Mountains with Skyline Drive running its length

A deep river gorge known for whitewater, sandstone climbing and a giant steel arch bridge

Waterfalls, sandstone ledges and a historic canal towpath between Cleveland and Akron

Lake Michigan beaches, tall sand dunes and surprising plant diversity near Chicago

Historic bathhouses, steaming thermal springs and wooded trails right in a downtown

The world's longest known cave system under quiet Kentucky hills and rivers

Old-growth floodplain forest with some of the tallest trees in the eastern US

A vast subtropical wetland of sawgrass, mangroves and alligators at the tip of Florida

A mostly underwater park of coral reefs, mangrove shores and keys within sight of Miami

A huge brick fort on a tiny island 70 miles west of Key West, ringed by reefs

Striped buttes, spires and mixed-grass prairie rich in fossils, bison and bighorn sheep

One of the longest caves on Earth, famous for boxwork, under bison-filled prairie

Colorful North Dakota badlands where bison and wild horses roam and a young TR ranched

A water park of big lakes, rocky islands and northern lights on the Canadian border

A roadless wilderness island in Lake Superior, reached only by ferry, seaplane or private boat

The 630-foot stainless steel Arch on the St. Louis riverfront, with a free museum below

North America's tallest sand dunes, piled against the Sangre de Cristo Mountains

A sheer, narrow gorge of ancient dark rock plunging up to 2,700 feet to the Gunnison River

Ancestral Pueblo cliff dwellings tucked into canyon alcoves on a high, forested mesa

Colorful badlands of the Painted Desert and fields of 200-million-year-old petrified logs

Two desert districts on either side of Tucson, filled with giant saguaro cactus forests

Wave after wave of brilliant white gypsum dunes in the Tularosa Basin

A huge limestone cave system under the Chihuahuan Desert, plus a nightly summer bat flight

Texas's highest peaks rise from an ancient fossil reef above the Chihuahuan Desert

Remote desert park where the Rio Grande carves deep canyons below the Chisos Mountains

Quiet Nevada park with a 13,000-foot peak, ancient bristlecones, a marble cave, dark skies

Steaming hydrothermal areas, a climbable volcano and alpine lakes in Northern California

The world's tallest trees, wild beaches and Roosevelt elk on California's far north coast

Volcanic rock spires, talus caves and soaring California condors in the Gabilan Mountains

Five wild, boat-access-only islands off the Southern California coast with sea caves and island foxes

Jagged, glacier-covered peaks, turquoise lakes and deep forest a few hours from Seattle

Six million acres of tundra, grizzlies and North America's tallest peak along one road

The largest US national park, with huge glaciers, high peaks and a copper mill town

A roadless bay of tidewater glaciers, rainforest and whales, reached only by air or sea

Glacier-carved fjords spilling from the Harding Icefield, next to the town of Seward

Brown bears fishing for salmon at Brooks Falls and a valley buried by a 1912 eruption

Volcanoes, turquoise lakes, coastal bears and Dick Proenneke's handmade cabin

Roadless Brooks Range wilderness above the Arctic Circle, reached only by air or on foot

Arctic sand dunes, a wide wild river and one of the great caribou migrations on Earth

A 10,023-foot volcano summit above the clouds on Maui, plus rainforest pools near Hāna

Two of the world's most active volcanoes, with an ongoing Kīlauea summit eruption

Rainforest ridges, coral reefs and village life on three South Pacific islands

White-sand bays, coral reefs and sugar mill ruins covering most of St. John