Rock the Park - Season 2

One of the last undeveloped beaches on the Atlantic coast is home to a lot of wildlife, including manatees, manta rays, alligators, and wild horses.

Dry Tortugas National Park; one of the largest coral reefs in the world; stingrays, goliath grouper and nurse sharks.

Black bears; tiny creatures under rocks; a hike to the top of a Smoky Mountain peak.

Wind surfing; endangered sea turtles hatch.

Iconic sea caves carved into the cliffs of Lake Superior; a 100-year-old shipwreck.

Jack Hanna joins the guys on a hike through bear country; a good look at a grizzly; taking on rough white-water rapids.

Riding the white water in Alaska's Aniakchak National Monument.

Traversing a crevasse-laden glacier to take on an Alaskan peak in Denali National Park.

Exploring lava caves and cinder buttes in what may be the strangest 75 square miles in North America, in Idaho.

Hoping to spot all of Denali's big five; sled dogs and pups in training.

U.S. Secretary of the Interior Sally Jewell hikes up Mount Rainier.

Climbing the Grand in Grand Teton National Park.

The Rockies by hoof and by foot; rock-climbing a rock formation called the Twin Owls.

Capitol Reef National Park in Utah; the history of the first settlers.

Colton and Jack head to Maine's Rocky Coast for a taste of Acadia National Park.

Custer State Park; Jewell Cave; Badlands National Park.

Texas: rattlesnakes, intense heat and the Rio Grande's Rock Slide.

A bioluminescent bay; a wall dive into the abyss.

St. John, the U.S. Virgin Islands; a night scuba dive.

Trekking up the tallest peak in Great Basin National Park; a wild caving mission.

Yosemite National Park in California; reducing trash going to landfill.

Grizzly bears; bison; salamanders; baby sea turtles.

Shooting rapids; diving deep; kayaking caves; climbing ice.

A look back at Jack and Colton's greatest adventures and the varied landscapes of the national parks.

Whale-watching; surfing; the Chasm of Doom.

A winter adventure in the Yellowstone National Park.