The concrete and steel high-rises, stone jetties and pavement of Ocean City; or the drifting sand, shrub thicket and salt marsh of Assateague.
From half a mile high there is no doubt which domain seems more stable and durable: Assateague wins because Ocean City looks so anemic.
"It takes people by surprise. Their first comments are almost always how narrow, how fragile the city looks," says Greg Von Rigler, owner and operator of Sky Tours out of the resort's airport in West Ocean City.
Mr. Von Rigler, a former lifeguard who began flying for a living about six years ago, is hardly the first pilot here to give sightseeing tours. But he is probably the first to include a solid ecological commentary on the complex dynamics of the barrier island system as it unfolds below. A flight in his four-seat Cessna is a superb way to appreciate why such sand islands are among the Earth's most fluid of landforms.
From on high, he can point out the fantastic patterns made by shoaling sand, as the ocean moves it from the beach side to the bay side of the islands. This sand transport is how the islands survive and grow, even as they erode on their beachfront, Mr. Von Rigler explains. Dredging and bulkheading in 10-mile-long Ocean City tends to offset this natural process. Most of Assateague's 37 miles feature dramatically broader meadows, forests and marshes behind its beach.
If customers opt for a long trip (half an hour), Mr. Von Rigler likes to show them the narrow, sand-starved northern tip of Assateague (its sand diet blocked by Ocean City's inlet), and then head down to Tom's Cove at Chincoteague, where sand is accumulating so fast the "hook" there has grown more than two miles in this century. "Then it really hits them how dynamic and connected a system this place is," the pilot says.
Mr. Von Rigler says he never tires of the aerial view, because so much is always changing. Summer brings porpoises and giant manta rays -- 20 feet across the wingtips -- into the shallows. Deer and pony trails have worked complex webs into the marshes and bayberry thickets. The whole beach changes markedly in winter, because the winds of nor'easters create a choppy type of wave that erodes the sand dramatically.
For the most part, the sand along Maryland's coastline has only moved offshore a short distance, remaining in what geologists call "the active beach." The beach that is visible, like the tip of an iceberg, is only about 10 percent of the active beach.
The aerial viewpoint reveals colors and textures not conceivable from the ground. The miles of marsh and water, intricately twined, spread a perfect linen for the artistry of sunlight and wind. In one extraordinary section along the back of Assateague National Seashore, the bluish waters of shallow tidal creeks cut into the green felt of marsh like the leaping flames of some fierce, cool fire.
Mr. Von Rigler's high-wing Cessna is a good plane for unobstructed aerial photographs. Charges for sightseeing (year-round) run $17 a person for 15 minutes, and $33 for half an hour. The longer flight gives you a good look at Ocean City and several miles of Assateague. With the shorter flight, you can choose to see Ocean City or Assateague. Contact Sky Tours at (410) 289-TOUR.