In shape, Mount Desert Island resembles a lobster claw. Many of Acadia's best-known attractions are on the eastern side of the "claw," which is separated from the western side by Somes Sound. The park's western half features five mountains, numerous salt marshes and nature trails, and some of the best bird-watching in New England. The remainder of Acadia National Park consists of the dazzling Schoodic Peninsula and several offshore islands, including Baker Island and remote Isle au Haut.

Many of the following natural attractions are found along Park Loop Road, a 20-mile, two-lane thoroughfare that winds through the eastern half of Mount Desert Island. It is accessible from the Hulls Cove, Cadillac Mountain, Sieur de Monts and Stanley Brook entrances. While you can drive the loop in under an hour, most visitors find that it takes at least a half of a day to take in all that this scenic route has to offer.

The shoreline section of Park Loop Road is the most heavily traveled in Acadia, and for good reason. The road offers marvelous views of Frenchman Bay, as well as front-row seats to the pitched battle between land and sea. Most of the road's scenic highlights can be seen by car. To experience them, however, get out and walk the rolling footpath that winds alongside Park Loop Road.

In this otherwise rock-bound park, Sand Beach is a graceful anomaly. Located at Newport Cove, 10 miles from the visitor center, this is the park's only sand beach on the ocean. Swimming at Sand Beach is not for the faint of heart, ocean temperatures seldom climb above 55°F. (Warmer waters for swimming can be found on the western side of the island at Echo Lake, Acadia's other beach site.) A short hike inland from Sand Beach is The Beehive, a 520-foot-high mountain with a honey-combed eastern face sculpted by glaciers. The Beehive can be glimpsed from Park Loop Road.

Another feature you can see is Thunder Hole, located along Park Loop Road midway between Great Head and Otter Cliffs. Timing is everything here. As wind-driven tides sweep into this narrow granite channel, air becomes trapped, escaping with a thunderous report. At low tide on a calm day, Thunder Hole is stubbornly silent. Just south of Thunder Hole are Otter Cliffs, 100-foot-tall, pink granite buttresses rising straight out of the water.

Marked only by a simple set of wooden stairs leading down to the water, Little Hunters Beach is often overlooked by motorists in search of grander vistas. But this is one of Acadia's most peaceful and sheltered spots, a steeply pitched cove lined entirely with cobblestones, small, egg-shaped rocks polished by the pounding surf (no collecting, please).

In a park dotted with glacier carved ponds and lakes, Jordan Pond is perhaps the loveliest. Located on the western side of Park Loop Road, its waters are clear and cool. Its shores are flanked by Penobscot Mountain to the west and Pemetic Mountain to the east, both accessible by hiking trails. The view that sets Jordan Pond apart lies to the north, and rising from the shore are a pair of rounded mountains, aptly named The Bubbles.

Whether driving from Park Loop Road to the top of its 1,530-foot summit or hiking up one of the trails, most visitors consider Cadillac Mountain the high point-both literally and figuratively-of their trip to Acadia. Not only is Cadillac the park's highest peak, but it is also the tallest mountain on the Atlantic coast north of Brazil. On a clear day (visibility is best during fall and winter), the views Cadillac commands are panoramic and unparalleled. Spread out below are island-dappled Frenchman and Blue Hill bays, the whole of the park, and beyond that, much of Maine itself. Some visitors arrive at dawn, for Cadillac is one of the first places in the United States to see the sun rise, others prefer the mountain's equally dazzling sunsets. Whenever they come, most visitors spend hours clambering over the bald granite dome.

Neatly bisecting the eastern and western halves of Mount Desert Island, Somes (rhymes with "homes") Sound is the only fjord on the East Coast of the United States. A more poetic meeting of land and sea is hard to imagine. Steep mountains line both sides of the sound which is comprised of a narrow, 168-foot-deep gorge of salt water carved by glaciers. The best views of Somes Sound, other than from a sailboat or from Acadia Mountain, are from the southbound side of Sargent Drive (off Route 198), which closely hugs the sound's eastern shore.

The western side of Mount Desert Island is the more tranquil half of the park. Less visited and congested, it also affords visitors wonderful views of Somes Sound and the mountainous eastern portion of the park. Located on a narrow stretch of Route 102A, between a small pond and a broad expanse of bay, Seawall faces the Cranberry Isles and the Atlantic Ocean. This is an ideal spot for watching many seabirds.

Bass Harbor Head Light, which rises from the rocky, southernmost tip of Mount Desert Island, is one of the most photographed lighthouses on the East Coast. The light, which was built in 1858, marks the entrance to Bass Harbor and, beyond it, Blue Hill Bay. Now fully automated and managed by the U.S. Coast Guard, it is the only park lighthouse accessible by car. The lighthouse is located on the western side of the island, on Route 102A. Note: RVs are not allowed on the road to the lighthouse.

In 1901, a group of wealthy Mount Desert Island summer residents banded together to set aside the land that would later become Acadia National Park. One of the park's early benefactors was John D. Rockefeller, Jr., the millionaire industrialist and philanthropist who later planned and built New York City's Rockefeller Center. Rockefeller hoped the land would one day become "a real gem of the first water among national parks," but, in 1913, that hope was threatened by an unforeseen menace: the arrival of the automobile on Mount Desert Island.

Rockefeller, however, did not take this threat lying down. Over the next 27 years, he built a system of carriage roads crisscrossing his property, most of which he later donated to the park. Gently graded and lined with broken stone, the "Rockefeller Roads" (as they were known) offered a refuge from the "horseless carriage" for hikers, horseback riders and the open, horse-drawn carriages, which were the summercators' preferred mode of travel. Linking the 45 miles of carriage roads were a series of handsome bridges that were built with local granite and cobblestones. The Rockefeller Roads were not without controversy, however, some summer residents considered them a scar on the wilderness.

Today, now that the automobile has all but conquered the island, visitors to Acadia can be thankful for Rockefeller's generosity and foresight. Winding through the eastern half of the island, past lakes and mountains, these roads are now enjoyed by hikers, joggers, cyclists, cross-country skiers and carriage riders. Wildwood Stables, located on Park Loop Road, offers six rides a day in open carriages drawn by sturdy Percheron and Belgian draft horses. From mid-June to Columbus Day, a sunset ride to the summit of Day Mountain is offered. Reservations are strongly recommended. For visitors with disabilities, two carriages can now accommodate two wheelchairs each.

Although Wildwood Stables no longer offers horseback rides, it is possible to vacation at Acadia with your own horse. The stables rents both space and campsites to visiting equestrians. For more information about carriage rides and rentals of stall space and campsites, call the stables at (207) 276-3622.

Fifteen miles southwest of Mount Desert by boat, at the mouth of Penobscot Bay, lies Isle au Haut, the wildest and most remote section of the park. Accessible by a 45-minute mail boat ride from the village of Stonington (no car ferries are available), Isle au Haut rewards those who make the trip with hiking trails, spruce forests, cobblestone beaches and unobstructed views of the Atlantic.

By comparison, Schoodic Peninsula is a model of accessibility, located just one hour by car from Bar Harbor, off Route 186. Still, this 2,000-acre peninsula (Acadia's only wedge of the mainland) does not attract the large numbers of visitors who visit Mount Desert Island. Thus, visitors to Schoodic can freely explore the six-mile park road, a 440-foot-high headland, various hiking trails and the area's cobblestone beaches. If a crowd collects anywhere, it is usually at high tide at the granite-and-basalt ledge called Schoodic Point. The point, which confronts the sea head-on, unprotected by any offshore islands, fully merits the word spectacular. Full of sound and fury, wave after relentless wave hurls itself at the shore, sending plumes of ocean spray into the air - surely one of Acadia's most spellbinding sights.

There is no symbol of the Maine coast more stirring than the lighthouse. Whether rising tall on the mainland or on a tiny scrap of rock many miles out to sea, these beacons have guided mariners through Maine's many rocky ledges and pea-soup fogs for more than 200 years. Maine is second only to Michigan in its number of lighthouses. More than 60 are found from Cape Neddick Light at the state's southern tip to the West Quoddy Head Lightway Down East.

Maine lighthouses were originally manned by a lighthouse keeper and often by his family, as well. Romantic in the telling, the life of a lighthouse keeper (especially an offshore keeper) was, in practice, lonely and fraught with responsibility and risk. Today, all Maine lighthouses are automated and monitored by the U.S. Coast Guard. Some decommissioned lighthouses are being put to novel uses. For instance, Isle au Haut, the former Robinson Point Light is now the Keeper's House, a four-bedroom bed-and-breakfast.

Acadia boasts five lighthouses arrayed around the surrounding bays: Bass Harbor Head, Bear Island, Baker Island, Egg Rock and Great Duck Island. Built between 1828 and 1875, all the lighthouses except Great Duck are visible from various points in the park. Only Bass Harbor Head is accessible by car.