On August 25, 2016, the National Park Service will celebrate 100 years of preserving some of the country’s most beautiful spots. To mark the occasion, the NPS has encouraged travelers to visit as many parks as possible this summer.

There is plenty to see and do so to help we’ve identified the top 10 most popular national parks. Now that you’ve got a starting point, you can look through the list to see what stands out to you to help make your decision. Will it be seeing the world’s largest dormant volcano? Taking an elevator down to an underground cave?

  1. Grand Canyon National Park, Arizona


A quintessential bucket list destination, Grand Canyon National Park stretches over more than 1,900 square miles of exquisite river valleys that are up to a mile deep and is considered one of the Seven Natural Wonders of the World. For a full-day guided tour of the canyon, travelers can try the Small Group Grand Canyon Day Tour from Flagstaff, which includes lunch and transportation to and from your hotel.

  1. Bryce Canyon National Park, Utah


Bryce Canyon National Park is home to the largest collection of hoodoos (a column or pinnacle of weathered rock) in the world. The 56-square-mile park’s unique blend of pine trees and rock formations make it a truly breathtaking spot. Try the Bryce Canyon Day Trip from Las Vegas to walk along the canyon rim and see the pink cliffs from Sunrise Point.

  1. Grand Teton National Park, Wyoming


Grand Teton National Park features over 200 miles of trails and is known for the picturesque Teton Range, whose nine peaks are part of the Rocky Mountains. There are plenty of good views here – unlike most mountain ranges, the east side of Teton lacks foothills, making it easy to see the whole range. Animal lovers will enjoy the Grand Teton Small-Group Wildlife Safari by Jeep, a four-hour tour that takes visitors to the best wildlife-viewing spots in the park.

  1. Haleakala National Park, Hawaii


Travelers are able to experience a unique blend of volcanic landscapes and lush rain forests at the beautiful Haleakala National Park. Visitors from around the world come to the park each year to catch the sunset from the top of Haleakala Crater, a dormant volcano that looms 10,000 feet above the island of Maui. Travelers willing to rise early can enjoy the Maui Haleakala Sunrise Bike Tour.

  1. Glacier National Park, Montana


Featuring more than 700 miles of trails, forests, meadows, lakes and mountains, Glacier National Park is a true nature lover’s paradise. The park is part of the “Crown of the Continent,” the largest intact ecosystem in the U.S. Glacier Park Red Bus Tours is popular among travelers for its informative commentary and unique transportation – travelers get to ride in style in vintage 1930s buses.

  1. Mesa Verde National Park, Colorado


Step back in time at Mesa Verde National Park, which is home to some of the best preserved Ancestral Puebloan archeological sites in the country. History buffs will enjoy exploring the park’s tree-covered plateaus and 600 cliff dwellings. Travelers who want a deep dive into the culture, architecture and lifestyles of the original inhabitants can book a spot on the 700 Years Tour.

  1. Sequoia and Kings Canyon National Park, California


Visitors to Sequoia and Kings Canyon National Park get the best of both worlds. The two parks lie side by side in the southern Sierra Nevada and feature some of America’s most impressive natural landscapes. Get up close and personal with the world’s largest trees and the deepest canyon in the U.S. with Sequoia Sightseeing Tours. 

  1. Yosemite National Park, California


Yosemite National Park may cover almost 1,170 square miles, but the majority of visitors spend their time exploring just seven – almost 95 percent of the park is dedicated wilderness. The park is known around the world for its granite cliffs and thunderous waterfalls and offers ample hiking and camping opportunities. Travelers have the choice of a guided hike or can explore the park on their own with the popular Yosemite National Park Day Trip from San Francisco.

  1. Zion National Park, Utah


Spanning over 229 square miles, Zion National Park is home to 289 species of birds, 75 mammals and 32 reptiles across its four unique life zones. Take in the impressive sandstone cliffs, canyons and natural arches with the Zion National Park Day Tour from Las Vegas.

  1. Carlsbad Caverns National Park, New Mexico

Unlike most of the parks on this list, the best features of Carlsbad Caverns National Park are underground – more than 119 known caves sit below the surface. Reachable by foot or by elevator, Carlsbad Cavern is almost 4,000 feet long, 625 feet wide and 255 feet at the highest point. Get up close and personal with the stalactites and stalagmites on the free self-guided Carlsbad Caverns Natural Entrance Tour.