TWICE AS LARGE as all the other Hawaiian islands put together, the Big Island requires a strategic plan. Spend part of your vacation based on the sunny Kona or Kohala coasts, splashing and snorkeling in the aquarium-like waters. Then spend your remaining time based around Hawaii Volcanoes National Park, where you can view flowing lava and explore rainforests. By establishing two separate base camps, you'll get a sense for the island's stunning diversity and avoid those wilting out-and-back days in the car.
ACTIVITIES Under a canopy of coconut palms and wood-carved tikis, Pu'uhonua O Honaunau National Historical Park ($5 per vehicle; 808-328-2288, www.nps.gov/puho) is 182 acres of archaeological remains, including temple platforms and coastal village sites. Try your hand at making kapa cloth (pounded wauke bark) or paddling an outrigger canoe at the annual Hawaiian Cultural Festival in late June.
Paddle a sea kayak across calm, one-mile Kealakekua Bay from Captain Cook's Monument, where the man himself landed in 1779 and where spinner dolphins like to play. Contact Kona Boys (808-328-1234, www.konaboys.com) for rentals ($25 per single kayak per day) or guided day trips ($95 per person).
Plan to spend at least two full days in Hawaii Volcanoes National Park ($10 per vehicle; 808-985-6000, www.nps.gov/havo). View the molten lava at the end of the Chain of Craters Road, then check out the stone fireplace in the Volcano House Hotel (808-967-7321), where the fire has been burning nonstop since 1874! Try the three-mile Kilauea Iki Trail, which will take you through a fern- and-ohia rainforest before dropping into the crater of Kilauea Iki.
Hawaiian Walkways ($95 per person, $75 for kids 8-12; 800-457-7759, www.hawaiianwalkways.com) offers guided day hikes along the rim of the remote Waipio Valley. Look for the Hawaiian hawk as you trek past bamboo orchids to a hidden, unnamed 40-foot waterfall and swimming hole.
Bodyboard or bodysurf the shore break at Hapuna Beach in South Kohala. Summer's small waves are also ideal for skimboarding. Because day rates for rentals add up, pick up a boogie board at Costco in Kailua ($40; 808-334-0770), then spread aloha by giving your board to a local youngster before you leave the island.
FOOD Try the broiled mahi-mahi plate at Kona Mixed Plate (808-329-8104).
Get treated to table-side hula and passion-fruit tea at Bamboo Restaurant and Gallery (808-889-5555).
Kids love the chicken satay and parents the incendiary curries at Thai Thai (808-967-7969).
LODGING The 62-acre Hilton Waikoloa Village is on the sun-drenched Kohala coast ($200 per night, kids under 18 free; 866-223-6574, www.hiltonwaikoloavillage.com). Kids can't get enough of the 175-foot water slide, three swimming pools, and protected snorkeling lagoon at this oceanfront resort.
The Chalet Kilauea Collection ($49-$399 per double per night; $15 for kids under 16; 800-937-7786, www.volcano-hawaii.com), in Volcano Village near Hawaii Volcanoes National Park, offers a range of accommodations, from six thrifty B&B-style rooms to four lodges to five vacation homes. Our favorite is the Ohia Hideaway Cottage, a one-bedroom cabin secluded in the rainforest.