Be sure to pack some SPF and your snorkel before venturing down to the only national park south of the equator (approximately 2,600 miles southwest of Honolulu) that includes three volcanic islands and two atolls. The coral reefs here, which have the greatest biodiversity of any park in the United States, are heaving with almost 900 species of colorful fish like the raccoon butterflyfish, clown triggerfish and guineafowl puffer. (Olosega and Ofu islands are your best bet for top-notch coral reef preservation and near-perfect snorkeling conditions.) But you can also be completely idle: The National Park of American Samoa, which received only 10,440 visitors in 2014, has plenty of spotless shoreline for you to worship the sun or set up a romantic beach picnic.

When to Go: Balmy year-round temperatures make this national park in the South Pacific Ocean easy around the calendar.

With its sky-high Chigmit Mountain peaks, two active volcanoes, alpine tundra, and turquoise lakes brimming with salmon and so smooth they double as mirrors, Lake Clark National Park really is The Last Frontier. The park is only accessible by small aircraft or boat (just 11,639 visitors came in 2012 compared to Yosemite's nearly 4,000,000), so this area remains unblemished, and it offers magnificent wildlife sightings of brown and black bears, moose, caribou and Dall sheep. Furthermore, the 4,030,005-acre national park allows catch and release fishing and species of salmon including the chum, king, coho, pink and sockeye spawn in all main rivers between the months of June and September; it is estimated one-and-a-half million to six million sockeye salmon enter the Lake Clark watershed every year via the Newhalen River. Other outdoor pursuits on offer are rafting (don’t expect white rapids, though), kayaking and hiking through the Tanalian Trails network.

When to Go: Summer, when the average highs fluctuate between 50 and 65 degrees.

Poking out of Lake Superior near the Canadian border, Isle Royale National Park is at least 14 miles from the mainland at its closest point and only accessible via seaplane or boat. Its exceptional ecosystem landed it on country’s International Biosphere Reserve list in 1980, so expect to see species like moose, gray wolf, snowshoe hare and over eight varieties of bat. In addition to great hiking (don’t miss the Greenstone Ridge Trail for fall foliage), visitors can rent kayaks, canoes and motorboats at Windigo and Rock Harbor and circumnavigate the main 45-mile long island (which is edged by over 450 smaller islets) at their own pace. The national park closes during the winter and opens for tourists in mid-April each year; access points are from Grand Portage, Minn., on the Voyageur II and Sea Hunter, as well as Houghton, Mich., on the Ranger III, and Copper Harbor, Mich., on the Isle Royale Queen IV.

When to Go: Head there in the summer to kayak or canoe and the early fall to see gorgeous fall foliage.

Stretching to the northern limits of Washington State, North Cascades National Park answers your call of the wild with its grizzly and black bears, lynx, mountain goats, wolverines and more than 300 glaciers. Zealous climbers in tip-top shape can obtain a backcountry permit and dig their crampons and pickaxes into glacial masses or go mountaineering and ascend one of the many rugged peaks. Want something a little mellower? Veer off of North Cascades Scenic Highway (Route 20), where more than 15 trails beckon hikers of all abilities. One of the most popular day hikes is the Cascade Pass Trail (accessible by Cascade River Road), which rewards visitors with panoramic views of the behemoth glaciated mountains. Don’t leave North Cascades National Park without cruising on the 55-mile, slender Lake Chelan up to Stehekin to see the effusive 312-foot Rainbow Falls and breathtaking Agnes Gorge (note: this is definitely an overnight trip and there are a handful of accommodations available in the village of Stehekin).

When to Go: May through September offer moderate weather and average daytime highs of almost 72 degrees.

When Spanish explorer Ponce de Leon discovered these pristine islets approximately 70 miles west of Key West in 1513, he christened them Las Tortugas, which translates to “The Turtles,” because of the region’s plethora of green, loggerhead, hawksbill, Kemp's ridley and leatherback turtles. Fast-forward to today: The region is a scuba diver’s playground with shallow, cerulean waters, hundreds of shipwrecks and nearly 30 varieties of coral swarming with underwater favorites like the gray angelfish, red grouper, stoplight parrotfish and smallmouth grunts. The Yankee Freedom III offers daily day trips ($165 for adults) from Key West and it includes breakfast and lunch, a 45-minute guided tour of unfinished Fort Jefferson and a few hours for swimming and snorkeling. There’s a 10-site bare-bones campground ($3 per person, per night), but beware, campers must bring all supplies, including water and food, and all trash must be brought back to the mainland.

When to Go: November through April is the region’s dry season and temperatures are comfortable, hovering in the low to mid-70s.

Often dubbed the Galapagos of North America, time has allowed this unique archipelago off the coast of southern California to evolve into its own microcosm. Channel Islands National Park extends to five of the eight islands (Santa Cruz, Santa Barbara, Santa Rosa, San Miguel and Anacapa) and contains 145 plant and animal species found nowhere else on Earth. Set out in search of endemic terrestrial animals such as the night lizard, island gopher snake, island deer mouse or island fox, the largest creature in the island chain, yet one of the smallest canids in the world, tipping the scale at just five to six pounds. Botanists can have a field day identifying the almost 800 flora, while divers can delve below the chilly water to find arcane sea caves. But if you’d rather stay dry, you can hike, camp, kayak, fish and whale-watch as well.

When to Go: For wildflower viewing, visit in the springtime, but if you’re looking to partake in hiking or water sports you’ll want to head here in the late summer.

After an age-old lake dried up on the San Luis Valley floor, domineering southwesterly winds pushed the sand remnants toward the Sangre de Cristo Mountains, but coincidentally, winds from divergent directions shaped the sediment into the dunes you see today. Great Sand Dunes National Park features the tallest dunes in North America, and offers visitors the chance to sand board or sled down mounds of sand as high as 750 feet (Star Dune). Sand surface temperatures can reach a scorching 150 degrees on afternoon summer days, so it’s wise to sled the dunes in the early morning or late evening. Another claim-to-fame of the park is Medano Creek, which has a beach-like microclimate in the late spring and early summer months. Small surges of water create waves when shallow sand bed dams on the creek break and are great for tubing or wading. The park is especially kid-friendly, with junior ranger programs, but also has great hiking (Mt. Herard measures in at 13,297 feet and dwarfs the famous dunes below).

When to Go: Late April, May and early June to see the Medano Creek run (it goes bone dry come August and September).

Straddling the U.S./Mexico border (118 miles of which are along the Rio Grande River) and crammed with some 500 million years of history, this remote area in the Lonestar State’s Chihuahuan Desert is one-of-a-kind. Big Bend National Park, which gets its moniker from the dramatic change in direction of the Rio Grand River, is an open-air museum: The National Park Service estimates that there are nearly 26,000 archeological sites spread throughout the park, and some date as far back as 10,000 years. There are 200 miles of hiking trails ranging from easy to strenuous at Big Bend National Park, and two of the best to tackle are Santa Elena Canyon and Lost Mine. At 4.8 miles round-trip, the Lost Mine Trail weaves through the Chisos Mountains and offers incredible views of Juniper Canyon and Casa Grande. Summit the trail and you can even see the Sierra del Carmen in Mexico. For something a little shorter, try the Santa Elena Canyon Trail. The hike descends to the Rio Grande’s edge, where the limestone canyon walls soar 1,500 feet above the river. Come nightfall, amateur astronomers gaze up at the natural planetarium with their naked eye as 2,000 stars twinkle in the sky on the clearest of evenings.

When to Go: November through April before the sweltering summer heat arrives.

Redwoods dotted California’s northern coast as long as 20 million years ago, but by the 1960s, the logging industry decimated nearly 90 percent of the population. In a valiant effort to preserve the world’s tallest trees (at more than 300 feet), the Redwood National Park was created in 1968. The best way to comprehend the sheer scale of these giants is by foot, and hiking opportunities abound here. Some great, moderate hikes are the 4.2-mile James Irvine Trail, which brings visitors to Gold Bluffs Beach and Fern Canyon (as seen in The Lost World: Jurassic Park), as well as Miners Ridge Trail (this follows the course miners took during the California Gold Rush in the mid 1800s). For more agile hikers, the Tall Trees Trail (you’ll need a permit) is a three- to four-hour ramble and home to the tallest redwood on the planet. But, if you don’t have a lot of time to meander through the forest, try the Newton B. Drury Scenic Parkway; the National Park Service refers to this drive as the “not-to-be-missed alternative to U.S. 101” because it cuts straight through the old-growth redwoods, which began their long journey 2,000 years ago as teeny seedlings.

When to Go: Summer is the driest season to visit; shoulder season (spring and fall) has fair albeit drizzly conditions.

Created after a prehistoric volcano erupted and collapsed 7,700 years ago, Crater Lake is more than five miles in diameter and 1,943 feet deep, making it deepest lake in the United States. When the annual spring thaw arrives, an average 524-inch blanket of snow melts, trickling as far as 2,000 feet down into the piercing cobalt lake. The park becomes a flurry of activity each summer, with daily boat tours of the lake (reservations are strongly suggested and visitors should be prepared for an arduous 2.2 round-trip hike on Cleetwood Trail to the boat launch). Back on land, cyclists can spin their wheels around the rigorous 33-mile Rim Drive and hikers give their soles a run for their money on the 90 miles of trails. Those not looking burn calories while sightseeing can hop on the two-hour, ranger-led trolley tour, which circles the caldera rim seasonally (July to mid-October, weather permitting).

When to Go: Late spring and summer are the most ideal times; the park has seen measurable snowfall as early as September.

Ok, ok. We know the Grand Canyon is perhaps the most famous national park in the world. But it has more than a few secrets tucked within its immense expanse. Our favorite? Havasu Falls. There are no roads in, so your only route is on foot, via horseback or helicopter. We suggest taking the slow route, hiking 10 miles in to reach waterfalls and pools of brilliant turquoise water amid the warm glow of the orange- and red-hued rocks walls. Cool yourself in the pools, the mist of the waterfalls tickling your face, the roar of the water echoing off the canyon walls. Don't fancy the 10 mile hike out? Hire a horse or helicopter (generally less than $100 one-way) to take you out of the canyon.

When to Go: Early spring and late fall offer the best balance of fewer crowds and great weather, but the reward of a dip in the pools makes even a steamy summer hike worth it.

The article was written by Andrew Skwarek and originally appeared on Jetsetter.

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