#1 The Gateway Arch and Old Courthouse with a row of pink blooming cherry trees in front

Gateway Arch National Park

MO · 3.0M visitors/yr

Busy

Gateway Arch National Park is 0.14 square miles of westward expansion history beneath a 630-foot steel monument with three million visitors.

#2 A sunset creates a silhouette of a cypress tree with needle-like leaves that is shaped like an 'N'.

Everglades National Park

FL · 742K visitors/yr

Comfortable

America's largest subtropical wilderness—a slow-moving river creating sawgrass marshes, mangrove islands, and alligator habitat.

#3 Coral reef with two snorkelers diving below the surface

Biscayne National Park

FL · 512K visitors/yr

Busy

Miami's skyline floats on the horizon while you snorkel over the continental United States' only living coral reef system.

#4 A pink sky above gentle white buildings

Hot Springs National Park

AR · 2.5M visitors/yr

Very Crowded

Hot Springs' 143-degree thermal water flows through historic bathhouses where health seekers once shared sidewalks with gangsters.

#5 Saguaro flowers

Saguaro National Park

AZ · 946K visitors/yr

Very Crowded

Giant saguaros, some 200 years old and 40 feet tall, frame both sides of Tucson in the densest stands of these iconic cacti anywhere.

#6 View of the Congaree River during the Fall

Congaree National Park

SC · 242K visitors/yr

Moderate Crowds

The largest old-growth bottomland hardwood forest in the Southeast protects champion trees you'll reach via elevated boardwalk.

#7 Steep, rugged ocean cliffs extending in an island chain.

Channel Islands National Park

CA · 263K visitors/yr

Comfortable

California's Galápagos lies 12 miles offshore with 145 endemic species. Sea lions, island foxes, and rare seabirds inhabit five islands.

#8 Photo of Giant Dome and Twin Domes in the Big Room.

Carlsbad Caverns National Park

NM · 460K visitors/yr

Moderate Crowds

A 600-foot limestone cavern beneath the Chihuahuan Desert, carved by sulfuric acid rather than water, where 400,000 bats spiral out at dusk.

#9 Boulders in the Balconies Cave.

Pinnacles National Park

CA · 354K visitors/yr

Moderate Crowds

Volcanic spires rise above talus caves where you can crawl through darkness on designated routes. Half of Yosemite's crowds.

#10 Rocky coastline with palm trees and a cliff beyon

Hawaiʻi Volcanoes National Park

HI · 1.4M visitors/yr

Moderate Crowds

Two active volcanoes shape terrain from tide pools to alpine desert. Walk across recent lava flows and through rainforests on ancient rock.