1: 1. Yellowstone National Park - Bison roaming freely in their natural habitat. 2. Everglades National Park - Spot alligators in the wild. 3. Denali National Park - Grizzly bears and moose sightings.

2: 4. Grand Teton National Park - Witness majestic elk herds. 5. Great Smoky Mountains National Park - Black bears roaming in the forests. 6. Kenai Fjords National Park - Experience humpback whale sightings.

3: 7. Olympic National Park - Watch bald eagles soar in the sky. 8. Glacier National Park - Mountain goats and bighorn sheep sightings. 9. Redwood National and State Parks - Encounter playful sea otters.

4: 10. Big Sur Coastline - Gray whales migrating along the Pacific coast. 11. San Juan Islands - Orca whales breaching in the Puget Sound. 12. Custer State Park - Bison herds grazing in the grasslands.

5: 13. Great Bear Rainforest - Spirit bears and coastal wolves in British Columbia. 14. Katmai National Park - Brown bears fishing for salmon at Brooks Falls. 15. Katmai National Park - Brown bears fishing for salmon at Brooks Falls.

6: 16. Channel Islands National Park - Swim with sea lions and dolphins. 17. Joshua Tree National Park - Desert tortoises and bighorn sheep. 18. Zion National Park - Desert bighorn sheep climbing steep cliffs.

7: 19. Carlsbad Caverns National Park - Bat flight program at dusk. 20. Grand Canyon National Park - California condors soaring above the canyon. 21. Acadia National Park - Puffins nesting on the rocky cliffs.

8: 22. Everglades National Park - Anhingas and herons in the wetlands. 23. Shenandoah National Park - Black bears and white-tailed deer. 24. Great Sand Dunes National Park - Kit foxes and pronghorn antelope sightings.

9: 25. Rocky Mountain National Park - Elk bugling during the rutting season. 26. Yellowstone National Park - Wolf packs roaming the Lamar Valley. 27. Arches National Park - Golden eagles soaring above the red rock formations.