The Best National Parks to Visit in Summer

For travelers chasing sunshine, wild landscapes, and unforgettable vistas, summer is the prime season to hit America’s national parks. But with over 400 sites in the National Park System, deciding where to go can be overwhelming. The best national parks to visit in summer are those that strike a balance between breathtaking beauty and relative tranquility, offering accessible hiking, temperate weather, and iconic scenery.

While the big names like Yellowstone and Yosemite are always tempting, these seven national parks are best for a summer visit based on weather, scenery, and overall experience.

Glacier National Park, Montana

Best for: Alpine hiking, cool temperatures, and glacier-carved valleys

Glacier National Park earns its name for a reason. But these glaciers, while receding, still shape some of the most awe-inspiring terrain in North America. Summer is the only time of year when the full breadth of the park is open to visitors. The legendary Going-to-the-Sun Road—carved across sheer cliffs and alpine passes—usually opens in late June or early July, unlocking high-country access to Logan Pass and beyond.

Unlike the sweltering parks of the Southwest, Glacier remains cool and crisp in summer, making it ideal for full-day hikes without heat exhaustion. The scenery, from turquoise lakes to jagged peaks, reaches peak bloom in July and August.

Top Summer Activities:

• Hike the Highline Trail for panoramic mountain views.

• Boat across the glacial waters of Lake McDonald.

• Watch for mountain goats and grizzly bears in the alpine meadows.

Olympic National Park, Washington

Best for: Diversity of ecosystems, from beaches to glaciers

Olympic National Park is a microcosm of the Pacific Northwest’s natural wonders. Summer brings the driest and most accessible window to explore its three major ecosystems: rugged coastline, moss-draped temperate rainforest, and snow-capped alpine ridges.

No other park in the US packs this much ecological diversity into one place. In a single day, visitors can walk barefoot on coastal sand, trek through an ancient rainforest, and summit a mountain trail. Summer’s mild weather opens up access to nearly all of it.

Top Summer Activities:

• Walk the tide pools and sea stacks at Rialto Beach and Shi Shi Beach.

• Hike Hurricane Ridge for 360-degree mountain views.

• Explore the lush Hoh Rain Forest beneath a canopy of dripping moss.

Lassen Volcanic National Park, California

Best for: Geothermal features without the Yellowstone crowds

Snow lingers in Lassen well into late spring, so summer is the first chance to experience this underrated volcanic gem in full. By July, the main park road is open, revealing steaming fumaroles, lava fields, and boiling mud pots, all without the congestion of more famous geothermal parks.

This park blends the thrill of volcanic activity with alpine lakes and forested trails, all under the radar of most summer tourists. It is also part of the lesser-known Volcanic Legacy Scenic Byway, offering a quieter road trip route through Northern California.

Top Summer Activities:

• Hike to the summit of Lassen Peak for panoramic views and active geology.

• Explore Bumpass Hell, a hydrothermal area with boardwalks over bubbling earth.

• Stargaze in one of the clearest night skies in California.

Acadia National Park, Maine

Best for: Coastal views, ocean breezes, and sunrise vistas

Acadia comes alive in summer. The park’s scenic drives, ocean hikes, and historic carriage roads are all at their best when the skies are clear and the wild blueberries ripen. While it does see summer crowds, the temperate Atlantic weather and sea breeze make it a refreshing escape from the summer heat elsewhere in the US.

Few national parks offer a combination of mountain views and salty ocean air. Acadia captures the rugged charm of the northeastern coastline with the accessibility of a compact, well-maintained park. For those traveling the East Coast, it is also one of the easiest national parks to reach in summer.

Top Summer Activities:

• Wake before dawn to hike Cadillac Mountain and watch the sunrise over the Atlantic.

• Bike the gravel carriage roads past stone bridges and forests.

• Kayak the protected coves around Mount Desert Island.

North Cascades National Park, Washington

Best for: Dramatic alpine scenery without the crowds

North Cascades National Park is often overlooked, yet it delivers jaw-dropping mountain scenery that rivals the Alps. Many of its higher trails and scenic routes are only accessible during the brief summer window, when snow melts off the ridges and reveals subalpine lakes, glaciers, and wildflower meadows.

With fewer than 40,000 visitors a year, North Cascades is one of the least visited national parks, yet it contains over 300 glaciers and hundreds of jagged peaks. For those seeking solitude in a truly wild setting, it’s one of the most rewarding places to visit in summer.

Top Summer Activities:

• Hike to Cascade Pass or Sahale Arm for views of hanging glaciers.

• Paddle the turquoise waters of Diablo Lake.

• Camp in solitude at one of the park’s remote backcountry sites.

Great Sand Dunes National Park and Preserve, Colorado

Best for: Stargazing, sandboarding, and cool nights at high elevation

Midday temperatures at Great Sand Dunes National Park can exceed 90 degrees, but mornings and evenings are ideal for hiking and sandboarding. In early summer, snowmelt from the Sangre de Cristo Mountains feeds Medano Creek, creating a shallow stream at the base of the dunes where families can wade and cool off.

The contrast is striking—massive dunes up to 750 feet tall rise in front of alpine peaks, creating a surreal desert-meets-mountain scene. As the sun sets and the skies darken, the park transforms into one of the best stargazing spots in the country.

Top Summer Activities:

• Slide down the tallest sand dunes in North America on a sandboard.

• Splash and cool off in Medano Creek.

• Camp under clear skies in one of the best dark-sky parks in the country.

Isle Royale National Park, Michigan

Best for: Remote adventure, wildlife, and freshwater isolation

Accessible only by boat or seaplane, Isle Royale is one of the most remote national parks in the contiguous US. It’s open only from mid-April to October, and summer is the safest window to make the journey across Lake Superior. The isolation makes it an oasis for wildlife, including moose and wolves, and a paradise for backpackers.

There is no cell service, no roads, and no cars on Isle Royale. This is the park to unplug and immerse fully in nature. The cool weather and long daylight hours of summer make it the perfect time to experience the island’s wilderness.

Top Summer Activities:

• Backpack the Greenstone Ridge Trail across the island.

• Canoe or kayak the inland lakes.

• Watch moose in the wild without crowds or roadways.

Final Thoughts: Why These Parks Win in Summer

Summer can bring peak crowds to the national parks, but these destinations each offer a version of summer that feels like an escape rather than a hustle. Whether it’s the alpine isolation of North Cascades, the sea-kissed cliffs of Acadia, or the volcanic steam vents of Lassen, these parks thrive when the days are long and the trails are open.

Instead of baking in the desert heat or sitting in long car lines at the most popular parks, consider trading predictable itineraries for something more surprising. Summer may be the most popular travel season, but it’s also when these national parks shine their brightest.

Best Summer National Parks by Experience

FAQs About Visiting National Parks in Summer

Which national park is the least crowded in summer?

Isle Royale National Park and North Cascades National Park both see far fewer visitors than better-known parks, offering peaceful experiences even in peak months.

What’s the best national park for avoiding extreme heat?

Glacier National Park, Olympic National Park, and North Cascades National Park all offer mild temperatures, even in July and August.

Can I see wildlife in these parks during summer?

Yes. Summer is prime time for spotting moose in Isle Royale, black bears in Olympic, and mountain goats in Glacier. Always observe wildlife from a distance and follow park safety guidelines.

What gear should I bring for a summer trip?

Pack layers, even in summer, especially in alpine parks where temperatures can drop at night. Bring sun protection, bug spray, plenty of water, and a map or GPS device for remote trails.

Are these parks family-friendly?

Absolutely. Acadia and Great Sand Dunes, in particular, offer activities perfect for kids, from biking flat carriage roads to splashing in creeks.