Floating face down in the Caribbean, with snorkel clenched in your mouth, lacks the structure, the regimentation, of observing the natural world in the way we’ve grown up to accept while walking through a forest, strolling through a meadow, or hiking up a mountain.

Insert yourself into this aqueous world and you encounter clouds of neon 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.

Fifteen or so feet beneath us on the bottom of Salt Pond Bay a green sea turtle cruises, smooth strokes of its flippers propelling it along. Here and there it pauses to graze on the seaweeds sprouting from the sandy floor. Moments later we happen upon a nurse shark parked on the seabed. Curiosity replaces concern as we gaze at this roughly 4-foot long predator, which turns with a flick of its tail and disappears deeper into the bay.

For most of us growing up in a world of flowers, birds, green grass between the toes and trees to climb, slipping beneath the Caribbean’s surface presents a new world that, while at times slightly uncomfortable, opens up vistas not found on solid ground.

Great Barracudas, despite their advance publicity, really don’t seem quite as scary as you’d think when you’re staring at them through a snorkel mask. These long, sleek, silvery carnivorous torpedoes of the deep just seem to hunker and wait, rocking slightly back and forth with the currents, seemingly taking life as it comes to them. But that doesn’t mean I didn’t keep a reasonable viewing distance while moseying myself about the coral reefs that rim Virgin Islands National Park.

Frankly, of greater concern to me were the Spiny Sea Urchins found throughout many of the park’s waters. These shiny black sea creatures with their 7-8-inch long spines that all the guidebooks say are hard, if not impossible without surgical intervention, to remove once impaled on your foot or finger got my full attention. The last thing I needed on my trip to paradise was to get too close to these pin cushions.

And the national park does indeed seem like paradise. While St. Thomas might be the cruise capital of the U.S. Virgin Islands, St. John is where you head to flee the mongering hordes. Indeed, I recall reading that St. John’s year-round population is just under 5,000, while St. Thomas’ is about ten times that. Of course, throughout the course of a year you do have to share St. John's relative solitude with nearly 500,000 national park visitors on an island that’s roughly 20 square miles. But if you’re even a little determined to manage the crowds on this Caribbean Sea outcrop, you can do it with relatively little effort.

For starters, there are beaches around just about every corner, and those beaches are of the postcard variety: shimmering turquoise waters, white sand, palm trees, brown pelicans and frigate birds patrolling the skies, heavily forested atolls dotting the ocean in most directions you look.

Trunk Bay is the showcase "chamber of commerce" beach that everyone who visits the national park wants to lay down on, the one in all the splashy advertising for St. John. Cinnamon Bay offers the only campground in the national park, one complete with showers, kayak rentals, restaurant, even a volleyball net stashed in the vegetation lining the beach.

But those are just the calling-card beaches at Virgin Islands National Park. You’ve also got Hawksnest Beach, Jumbie Bay, Little Maho Bay, Waterlemon (not Watermelon) Beach, Leinster Bay, Caneel Bay, Lameshur Beach (Great and Little), Salomon, Gibney’s, Francis Bay, Peter Bay, Salt Pond Bay…get the idea?

And those are just beaches in the national park. Head outside the park boundaries to the Coral Bay area and you’ll find even more beaches lapped by either the Caribbean Sea or the Atlantic Ocean. Or a mix of the two.

What’s good to know about visiting this warm, sandy, palm-tree-lined Caribbean gem of the National Park System?

* Laurance Rockefeller, whose family dug deep into its pockets to benefit places such as Acadia, Grand Teton, and Great Smoky Mountains national parks, just to name a few, didn’t hesitate to write checks from his Jackson Hole Preserve, Inc., in the 1950s to buy up large swaths of St. John to provide for today’s Virgin Islands National Park.

* Though only about 7,000 acres, the park draws nearly 500,000 visitors a year. They come to soak up the sun on one of the beaches, to snorkel in the turquoise waters, to forget winter.

* You can’t easily navigate Virgin Islands National Park without renting a 4WD rig. The public transportation largely revolves about open-air taxis that might not always go where you want them to go when you want them to. And while there are plenty of two-door Jeep Wranglers and similar SUVs to be had, you’d probably be better off with a four-door model if there are more than two of you and if you have more than a couple bags.

* To say St. John is quite hilly is a gross understatement. Some roads you head down leave you feeling akin to being on a roller coaster – you know, you chug, and chug and chug to the top and then plunge down the next side (Throwing your hands in the air at the hilltop IS NOT recommended) without getting a good view of exactly where you’re plunging until you’re on that downhill ride. Yep, plenty of those experiences here.

They also drive on the left side of the road, which takes a little getting used to. I’m not talking about just getting used to steering your rig on the left-hand side. Rather, you need to reorder your entire mental-driving-a-car-frame-of-mind away from driving on the right side of the road and getting over – physically and cerebrally -- to the left side.

* Seriously consider renting a house, which marketers refer to as “villas.” Time your visit for the off-season and you can find a nice one for about $200 a night. When you consider the full kitchen, the laundry room, and the two or three bedrooms, and more than likely the deck and BBQ, you’ll appreciate being able to flee the resort life and save a little money cooking for yourself when the mood strikes.

* Speaking of cooking, the Fish Trap Restaurant and Seafood Market in Cruz Bay is a great place to pick up fresh seafood to take to your villa for grilling. The Star Fish Market complex on highway 104 a little south of downtown Cruz Bay not only holds a grocery (an expensive one, at that), but possibly the best wine and liquor store on St. John (a $1450 bottle of Hennessy cognac, anyone?), and there’s a drug store on the second level.

* Best beach? Trunk Bay.

* Best beach for snorkeling? Watermelon Cay, which is associated with Leinster Bay. Just be sure to swim out and around the small cay, or head off to a small rocky point on the east for the best coral reef displays.

* Best beach for snorkeling, lying about, and fleeing the crowds? Hands down that’d be Salt Pond Bay on the south reach of the island. Get there before 10 a.m. for a prime selection of shaded spots, some with picnic tables, to serve as the day’s base-camp. Swim either out to the rocky point below Ram Head or out to the nearly submerged rock outcrops near the bay’s mouth for great coral displays – Elkhorn and Staghorn corals, as well as brain corals, which look like, well, brains.

There also are beautiful, purple-hued sea fans waving in the currents, pillar corals, sponges, luminescent lime-green parrotfish with bright yellow spots on their tails, and a wide variety of damselfish. Most fish think little of your intrusion into their world, more than happy to mill about gazing at you as you gaze at them.

* The best hike would be down the Reef Bay Trail. Of course, there aren’t a lot of hikes in this park, but the mix of scenery, history, and wildlife – iguanas, deer, birds, and soldier crabs, make it a good path to take for a few hours.

* Best ruins? The Annaberg Sugar Plantation ruins are the most-visited, as they’re easy to access on the North Shore Road, but the Catherineberg ruins off the Center Line Road are somewhat off the beaten path and offer a somewhat better preserved windmill. The Reef Bay ruins might be the best preserved, as this mill continued to process sugar cane long after slavery was abolished and steam boilers drove the mills. There are many, many other ruins on the island. Watch for them as you cruise about.

* Best restaurant? There are plenty to choose from, but Rhumb Lines in the heart of Cruz Bay got my vote one night with its Sing’s 410 Steak, an incredible tender slab of beef tenderloin that's been splashed with a spicy Jamaican demi-glaze.

* Most unexpected wildlife? That’d have to be the wild donkeys or wild goats you’ll likely encounter roaming along the roads near Coral Bay.

* Best volunteer opportunity? Hook up with the Friends of Virgin Islands National Park. On Tuesdays and Thursdays they gather up all the volunteers who show up and run them around the island to help the Park Service maintain trails, uncover ruins, etc.

* Biggest problem? The trash that accumulates on some of the remote beaches, such as Leinster. It’s about a half-hour walk to the best spots on the beach, and there are no trash bins there and no restrooms. You can probably imagine what sort of problems that creates.

* Next biggest problem? Non-native critters such as wild donkeys, goats, and mongoose (mongeese?), which you frequently see darting across roads or lurking about beaches looking to snatch a meal from your picnic if you’re not careful. And there are feral cats and hogs.

* Exercise best comes in snorkeling, where you can get into that wonderfully warm water and go in search of the octopus's garden and all its resident sealife.

* Best guidebook my wife and I discovered during our stay: St. John: Feet, Fins & 4-Wheel Drive by Pam Gaffin. The book not only proved invaluable, but Pam's tips, descriptions, and advice were dead on. Pam also offers personally guided tours on St. John's. You can learn more at her web site..