Thank God for aristocracy. When John D. Rockefeller Jr. and his Gilded Age pals decided to share some of their private summer playground on Maine's Mount Desert Island, they donated what would become part of Acadia in 1919. Now the park's multisport options draw more than two million visitors to this dramatic chunk of coastline every year. Bikers cruise the 45 miles of gravel carriage roads, kayakers explore the coves and islands, hikers scramble up 1,530-foot Cadillac Mountain, and climbers scale the oceanside Otter Cliffs while Atlantic breakers slap the rocks 110 feet below.

EXPERT ADVICE: "The Maine Island Trail is sort of like the Appalachian Trail of sea kayaking," says Glenn Tucker, owner of Bar Harbor–based Coastal Kayaking Tours, referring to the 350-mile thoroughfare that connects 162 islands along the coast, including many around Acadia. One of the best stretches starts just south of the park in the town of Stonington and ends approximately 30 miles later on Mount Desert Island. Coastal Kayaking offers three-day trips, suitable for all levels of paddlers, with overnights on small islands.

CRASH PAD: The Maine Island Trail passes by the north side of Isle au Haut, but it's the south side of the island that's park property. The Duck Harbor campground there is Acadia's only remote island camping, so reserve ahead for one of the five ocean-view lean-tos. Access Duck Harbor by kayak or via the daily mail boat from Stonington, a 45-minute ride. From $16 one-way; isleauhaut.com

DETAILS: nps.gov/acad, 207-288-3338; Coastal Kayaking Tours, acadiafun.com