If you love exploring national parks but hate contending with the hordes of people you find at places such as Yellowstone and the Grand Canyon, you can visit some of these lesser-known undiscovered treasures. You’ll have them pretty much to yourself!

CAPITOL REEF NATIONAL PARK, UTAH

Located in Utah’s south-central desert, Capitol Reef is noted for its nearly 100-mile-long Waterpocket Fold, a buckling of Earth’s crust that occurred about 65 million years ago, exposing 270 million years of geologic layers of rock and sediment. The prehistoric layers have been eroded by wind and water over the centuries, forming sheer multicolored cliffs, massive domes, twisting canyons, spires and arches, huge red rock monoliths and narrow winding riverbeds. You can view them on a 16-mile round-trip paved scenic drive starting at the Visitor Center in the town of Torrey. Add some bumpy rides on unpaved spur roads into Grand Wash and Capitol Gorge for closer views, and hike for miles, if you like, from the trailheads into the rocky canyons. Campers can set up in a 71-site developed campground near the entrance or in more remote areas.

Information: Open daily. $7 per person for seven days, $15 per vehicle for seven days, $20 per campsite per night. NPS.gov/care

WIND CAVE NATIONAL PARK, SOUTH DAKOTA

This park features a spectacular underground cave in South Dakota’s Black Hills. The Wind Cave, named for its whistling winds, has about 130 miles of passages that contain rare geological formations such as “boxwork” (paper-thin calcite fins that look like honeycombs), “cave popcorn” (small white, knobby formations) and “frostwork” (needlelike growths that resemble big ice crystals). Be sure to take at least one of the ranger-guided tours of the cave, and drive the paved roads through the rest of the 33,000-acre park’s mixed-grass prairies and dense pine forests where you are likely to spot bison, prairie dogs and other wildlife. The park has a campground, which is open year-round.

Information: Open daily. There is no entrance fee, but cave tours range from $10 per adult to $30 (half price for children ages six to 16 and holders of Senior Access Passports), depending on length and difficulty. Campsites are $18 per night in warmer months…$96 the rest of the year. 605-745-4600. NPS.gov/wica

BISCAYNE NATIONAL PARK, FLORIDA

Within sight of downtown Miami, Biscayne National Park is 95% underwater, and the rest consists of a few tiny islands and a narrow piece of mangrove shoreline on the mainland. Its clear turquoise water teems with colorful fish and sea grass and is home to the world’s third-largest coral reef and the remains of many shipwrecks, so it is one of the best places in the country for snorkeling and diving. Unless you have your own boat, you must shuttle to the islands or reefs from the mainland on a boat operated by the park’s concession. You also can sign up for glass-bottomed boat tours or snorkel and dive trips or rent a canoe or a kayak. In addition, park rangers offer free guided canoe or kayak trips along the coastal edges and shallow bay waters. There are no overnight accommodations, but tent camping is available on two of the park’s islands.

Information: Open daily. Campsites are $25 per night for up to six people and two tents. Round-trip ferry to the campsite is $59 per person, with a two-passenger minimum. Concession boat tours are $39 to $149 per person (786-335-3644). NPS.gov/bisc

ISLE ROYALE NATIONAL PARK, MICHIGAN

Isle Royale National Park consists of one large island surrounded by more than 450 smaller islands in the northwest part of Lake Superior. It is a rugged, unspoiled wilderness preserve close to Minnesota and Canada, and it is one of the few national parks to close in winter. Accessible only by ferry, private boat or seaplane, it has no roads and no wheeled vehicles but 165 miles of hiking trails, a marina, a lodge, myriad campgrounds and miles of scenic coastline. Although it is among the least visited parks in the country, its campers stay an average of 4.1 days, the longest for any national park.

Information: Closed November 1 to April 15. User fees: $7 per adult per day, free for children age 15 and under…individual season pass, $60. There are four passenger ferries and one seaplane that offer service to and from the park. Fares and schedules vary, and reservations are recommended. 906-482-0984. NPS.gov/isro

LETCHWORTH STATE PARK, NEW YORK

Long known as the “Grand Canyon of the East,” Letchworth State Park, 35 miles south of Rochester, New York, may not be a national park, but it is as remarkable as many of them because of its waterfalls—three magnificent major waterfalls in a deep narrow gorge of the Genesee River and about 50 smaller ones along its tributaries. Hiking paths parallel the river, where you’ll see an abundance of migratory birds in the spring and fall.

The park has a museum (open from May 1 to October 31) that includes artifacts from the area’s original Seneca Indian inhabitants and early pioneers. There also are original log buildings, including a cabin built by Mary Jemison, an Irish immigrant kidnapped as a teenager by Shawnees and later adopted by the Seneca tribe. A historic restored inn on a cliff overlooking one of the large falls offers rooms and meals. The park also has a state-run lodge, cabins, campsites, swimming pool and snowmobile and horse trails.

Information: Open daily 6 am to 11 pm year-round. Entrance fee: $10 per vehicle weekends in early May to Memorial Day and daily from Memorial Day through October. Museum fees are $1 for adults and 50 cents for children age 12 and younger. Campsites are $24 to $26 per night and are available through the New York State Reservation System, 1-800-456-2267. LetchworthPark.com

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