Blue tang dart about a reef at Virgin Islands National Park/Susanna Pershern

Some 45 years after I first decided I wanted to scuba dive, I've finally obtained my PADI certification. In land-locked Utah. So where might I head to test my new skills? Let's take a look around the National Park System for the best dive spots.

Biscayne National Park, Florida

Why dive here? There's the Maritime Heritage Trail, which leads divers to six wrecks, "spanning nearly a century and a wide variety of sizes and vessel types." You can explore wrecks dating from 1878, when the Arratoon Apcar ran around and sank several "football fields" away from where workers were building the Fowey Rocks Lighthouse, to 1966, when the Mandalay, a steel-hulled windjammer, sank on New Years Day.

The loss of the Mandalay had to be felt dearly by its last owners, Windjammer Cruises, Inc.

Mandalay was beautifully outfitted in mahogany, brass, and ivory, and had a teak deck. Aft quarters were a suite of 2 rooms with an adjoining bath for the owner, 3 single staterooms, each with a bath, and a large guest room with an individual bath. Forward of the main mast were a large saloon and living room, 3 officer’s staterooms with a bath, and ample forecastle for 6 men with a washroom and shower. All bathrooms had hot and cold water and all waste connected to a complete sanitary system. There were electrical lights and fans and other electrical equipment, and every stateroom had individual ventilation.

If you visit this page on the park's website, you'll find more details and GPS coordinates for finding the wrecks.

Dry Tortugas National Park, Florida

While many folks no doubt set out to visit Dry Tortugas National Park 70-some miles off Key West to visit Fort Jefferson, there's an incredible world underwater to explore there.

You can find a wreck, the Avanti, which ran aground on Loggerhead Reef in 1901 and sank. But perhaps the main attraction is the colorful reefs with their equally colorful marine life.

Texas Rock

This area is almost due north of Garden Key in about 55 feet of water. It consists of a huge mound of coral that emerges from the sand at about 55-60 feet of water and rises toward the surface to a depth of about 35 feet. The reef is rather isolated and is surrounded by sand. It takes a full dive to swim around the mound.

As you slide over the side of your boat, you may be immersed in a cloud of fish that are stacked up from the top of the reef almost to the surface. At first glance, they seem to be a fluid extension of the coral. Because the mound protrudes from a much lower reef, it is a magnet for marine life. On the north side of the reef is a forest of deep water sea fans that will rival anything to be found in the Caribbean. If you carefully investigate some of the nooks and I crevices in this area of the reef, you will find some rare black coral.

For the underwater shutterbug, this is a great place to photograph corals. With the exception of elkhorn and staghorn, almost every species of stony coral can be found here. In fact, this area is used as a coral growth monitoring station for ongoing research. If you happen on some obviously manmade apparatus while exploring this reef, it is probably part of this program.

Snorkelers will find plenty to do at Dry Tortugas, as well. In the area known as "Little Africa," on the north side of Loggerhead Key, this shallow, protected area is wonderful for veteran, and newbie, snorkelers. The Park Service says that this area is populated with "juvenile barracuda, lobsters, corals heads, soft corals, and tropical fish..."

Virgin Islands National Park, U.S. Virgin Islands

I've snorkeled here before, so I've seen a preview of what awaits scuba divers. With more than 40 percent of the park's "landscape" under water, there are more than a few places to explore.

When my wife and I visited some years back, each day we would head to a different beach to snorkel from. We hit Cinammon Bay, Maho Bay, Saltpond Bay, Great Lameshur Bay, and part of Round Bay. And still there were bays we missed, including Trunk Bay with its Underwater Trail that provides a little education on marine life here.

No doubt, each of those bays could appeal as entry points for scuba divers. For some other ideas, stop at the park's visitor center at Cruz Bay and ask for a brochure that will point you to various snorkel and scuba destinations.

Of course, if you make the effort to reach St. John, you might consider spending a day at Virgin Island Coral Reef National Monument just off the eastern end of St. John. According to the Park Service, "(T)hese waters support a diverse and complex system of coral reefs and other ecosystems such as shoreline mangrove forests and seagrass beds."

Channel Islands National Park, California

This is a decidedly cold-water diving experience, with water temps in the 55-70 degree Fahrenheit range, but you won't find in the Caribbean or Florida the incredible kelp forests that you'll find at Channel Islands. According to park staff, "(T)hese activities are best done on Santa Barbara, Anacapa, and eastern Santa Cruz Islands. Due to extremely windy conditions on Santa Rosa and San Miguel, these activities should not be attempted on these islands by the novice or anyone who is not properly trained, conditioned, and equipped."

At Santa Cruz Island, "(F)or snorkeling and diving, the easiest kelp beds to access are the ones near the pier and those to the eastern end of of the bay." At Santa Barbara Island, "access to the water is only at the Landing Cove via a dock. There are no other accessible beaches unless you have a watercraft. Excellent watersports can be experienced at the Landing Cove. The underwater visibility is usually very good and the water is teeming with life."

For a rundown on diving at Channel Islands, check out this page and follow the links.

Other dive destinations in the National Park System, some of which are probably best only for experienced divers, include Cape Hatteras and Cape Lookout national seashores where there are many wrecks off-shore; Lake Mead National Recreation Area, one of the more popular freshwater dive destinations, in part because there's the wreck of a B-29 Superfortress Bomber in the lake (though diving on it is not currently allowed); and Cape Cod National Seashore, where in the past rangers have "led 1 ½-hour snorkeling experience in a freshwater kettle pond or a saltwater tidal creek."

For a more detailed look at diving opportunities in the National Park System, check out this page. 

And please be careful swimming around coral reefs so that your fins don't accidentally damage them. Also, the Park Service urges all snorkelers and divers to look for "reef safe" sunscreens, those that don't include oxybenzone, butylparaben, octinoxate and 4-methylbenzylidine camphor, all of which have been shown to cause coral bleaching even at low levels.