Travel just three hours outside of Seattle and you'll find yourself in North Cascades National Park, an alpine wonderland of waterfalls, glaciers and snow-capped peaks. The rugged scenery is home to lynx, mule deer, moose and black bears who emerge in the summers to feed on wild berries.
While Zion gets the lion's share of attention in Utah, Capital Reef National Park in the heart of red rock country is filled with scenic canyons, sheer cliffs and natural bridges, all waiting to be explored. If you only have a few hours, take a scenic drive through the park; visitors with more time to spare can embark on half- to multi-day hikes.
Off the coast of California sit the five islands that make up Channel Islands National Park. The geology of the islands – sea cliffs, caves and natural stone bridges – are impressive in their own right, but the real draw is the dizzying array of wildlife that call the islands home. See seals and sea lions basking in the sun, or look for gray whales breaching the surface on their annual migration.
In the largely untouched swaths of land that make up West Texas, campers and hikers will find the hidden gem that is Guadalupe Mountains National Park. This well-preserved fossil reef from the Permian Era is home to dramatic canyons and shady glades accessible via 80 miles of trails.
The word "haleakala" translates to "house of the sun," and the stark volcanic landscape that dominates the park fits the name. what's truly spectacular about Maui's Haleakala National Park is the diversity of ecosystems that exist here; within the same park, you'll sweat in the harsh sun of a volcanic crater, walk through a bamboo forest or trek through a subtropical jungle.
Wrangell-St. Elias National Park & Preserve, Alaska
The 13.2 million-acre Wrangell-St. Elias National Park – the largest in the country – is larger than the entire country of Switzerland, but it somehow garners less attention than Denali National Park. You won't find any marked trails or park buses shuttling visitors around, but what you will find is breathtaking scenery and nature at its wildest.
Theodore Roosevelt came to the badlands of North Dakota to hunt bison in 1883, an experience that influenced him for the rest of his life and led him to create five national parks and found the US Forest Service. Theodore Roosevelt National Park honors the memory of the environmentalist-President, and the landscape here teems with life, including bison, bighorn sheep, elk and wild horses.
If you're like many Americans, you've probably never heard of Isle Royale National Park, much less been there. That's partly because you have to cross a sizable part of Lake Superior by boat or seaplane just to reach the park. Once there, you'll find an untamed wilderness and a solitude found in few other places in the country. Hiking, canoeing, kayaking and even scuba diving await.
Nevada's Great Basin National Park actually encompasses some 90 basins and valleys, as well as 13,063-foot Wheeler Peak and the geologically fascinating Lehman Caves. While the park is one of the smallest and youngest in the national park system, it's home to some of our nation's oldest trees, bristlecones as old as 3,000 years.
When you're snorkeling the clear waters of Biscayne National Park, it's easy to forget you're so close to downtown Miami – the city's skyline is actually visible from the park. The largest marine park in the system, Biscayne National Park offers a wealth of water sports, including canoeing and kayaking through mangrove forests, fishing, sailing, snorkeling and scuba diving.