Slipping beneath the rippling surface of the Caribbean at Virgin Islands National Park is something not soon forgotten. Snorkeling in this aqueous world brings you face-to-fin with clouds of neon-hued blue tangs drifting nonchalantly by, while black-and-yellow striped sergeant majors flit about, lacking the tangs' more formal-appearing approach to life in the ocean. And when you pull yourself out of the Caribbean, you plop down onto some of the most idyllic beaches in the world, certainly among the most incredible in the National Park System: Brilliant white sands, coconut palms offering shade, the warm turquoise waters beckoning you to return to exploring rainbow-hued coral reefs.

A week is not enough to truly sample this park's beaches. From Trunk Bay, Hawknest Beach, and Cinnamon Bay to Little Maho Bay and Waterlemon Beach, Virgin Islands National Park seems to have a monopoly on the park system's best beaches. Fortunately, in light of the effort to reach the Virgin Islands, it does not. From the rocky shorelines of Acadia National Park off the coast of Maine to the cobblestone beaches of Olympic National Park in the Pacific Northwest you'll find a variety of beaches that invite a variety of activities.

Most of us find the 55-degree Fahrenheit (or less) waters off Acadia too cold for anything but a quick dip. But that doesn't prevent folks from gathering at aptly named Sand Beach, located just off the Park Loop Road less than a mile south of the park's entrance station. This sliver of sand lures enough folks to justify a lifeguard in summer, but only the truly hardy spent much time in the water. Still, the setting -- sand, surf, and Mount Desert Island's broad granite shoulders as a backdrop -- make this a great place for a picnic and quick dip.

The waters off Cape Cod National Seashore are much more reasonable when it comes to swimming, and the beaches much more expansive, than those in Acadia. Here you can choose from the somewhat gentle waters that lap Race Point near Provincetown, or try Coast Guard Beach or Nauset Beach where a heavier surf is perfect for wave jumping or mastering your Boogie Board. Want more solitude? Then set your sights on Head of the Meadow Beaches south of Provincetown or Cahoon Hollow Beach a bit further south. Any crowds you encounter can be avoided by simply walking up or down the surf line.

Olympic National Park offers a number of intriguing Pacific Coast beaches. Some are designated only by number, others tagged with names. Rialto Beach is the most accessible, as the Mora Road runs right to a parking lot above the beach. This is a great place not only to take the kids to search tidal pools for interesting marine-life but to explore Hole-in-the-Wall, a sliver of headland that juts into the surf. Years and years of pounding waves have carved a tunnel through the headland, and if you time your visit with the low tide you can walk through it. Just make sure to head back before the tide turns.

Between the two coasts you can find wonderful national park beaches in places such as Pictured Rocks National Lakeshore and Sleeping Bear Dunes National Lakeshore in Michigan, Apostle Islands National Lakeshore in Wisconsin, Indiana Dunes National Lakeshore in Indiana, and, of course, Utah's Glen Canyon National Recreation Area, which encompasses Lake Powell (Editor's note: Hear Kurt discuss some of these parks on the podcast "An Insider's Guide to Summer in the Great Outdoors"). Those are just the most obvious beach destinations in the park system. I've found some wonderful spits of sand and gravel in places such as Yellowstone National Park's Shoshone Lake, Grand Teton National Park's Leigh Lake, and Yosemite National Park's Tenaya Lake.

Just remember, though, some of these beaches lack lifeguards, so you're often on your own.

Kurt Repanshek is the author of several national park guidebooks, including National Parks With Kids. You can get a daily dose of national park news, trivia, and commentary by visiting This site tracks "Commentary, News, and Life in America's Parks." Along with offering travel tidbits for those visiting the national parks, the Traveler offers anecdotes, insights, and a place for park junkies to speak their minds and stay atop park-related issues.

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