Don’t forget bug spray when exploring this warm, moist region, beloved by mosquitoes, and be ready for passing showers—you’re in rainbow territory here. Note: Some sights below are in the North Hilo district, just south of the official Hamakua district, which shares its rural character.

Waipio Valley

This breathtakingly beautiful valley has long been a source of fascination, inspiring song and story. From the black-sand bay at its mouth, Waipio (“curving water”) sweeps 6 miles between sheer, cathedral-like walls some 2,000 feet high. The tallest waterfall in Hawaii, Hiilawe, tumbles 1,300 feet from its rear cliffs. Called “the valley of kings” for the royal burial caves dotting forbiddingly steep walls, this was Kamehameha’s boyhood residence; up to 10,000 Hawaiians are thought to have lived here before Westerners arrived. Chinese immigrants later joined them and a modest town arose, but it was destroyed in 1946 by the same tsunami that devastated Hilo and Laupahoehoe, though luckily without fatalities. The town was never rebuilt; only about 50 people live here today, most with no electricity or phones, although others come down on weekends to tend taro patches, camp, and fish.

To get to Waipio Valley, take Highway 19 from Waimea or Hilo to Highway 240 in Honokaa, and follow the highway almost 10 miles to Kukuihaele Road and the Waipio Valley Lookout, a grassy park and picnic area on the edge of Waipio Valley’s sheer cliffs, with splendid views of the wild oasis below.

To explore the valley itself, a guided tour is best, for reasons of safety and access. The steep road has a grade of nearly 40% in places and is narrow and potholed; by law, you must use a 4WD vehicle, but even then rental-car agencies ban their vehicles from it, to avoid pricey tow jobs. Hiking down the 900-foot-road is hard on the knees going down and the lungs coming up, and requires dodging cars in both directions. Most of the valley floor is privately owned, with trespassing actively discouraged. Note that unmarked burial sites lie just behind the black-sand beach, which is not good for swimming or snorkeling and has no facilities.

Instead, book a ride on the Waipio Valley Shuttle (www.waipiovalleyshuttle.com; 808/775-7121) for a 90- to 120-minute guided tour that begins with an exciting (and bumpy) drive down in an open-door van. Once on the valley floor, you’ll be rewarded with breathtaking views of Hiilawe, plus a narrated tour of the taro patches (lo‘i) and ruins from the 1946 tsunami. The tour is offered Monday through Saturday at 9am, 11am, 1pm, and 3pm; tickets are $59 for adults and $32 for kids 10 and under (minimum two adult fares); reservations recommended. Check-in is less than a mile from the lookout at Waipio Valley Artworks (www.waipiovalleyartworks.com; 808/775-0958), on Kukuihaele Road. Waipio Valley Artworks is also the pickup point for Naalapa Stables’ Waipio Valley Horseback Adventure (www.naalapastables.com; 808/755-0419), a 2 1/2-hour guided ride ($94) for ages 8 and up; see “Horseback Riding” under Active Pursuits.

All ages may ride the mule-drawn surrey of Waipio Valley Wagon Tours (www.waipiovalleywagontours.com; 808/775-9518), on a narrated, 90-minute excursion that starts with a van trip to the valley stables. Tours run Monday through Saturday at 10:30am, 12:30pm, and 2:30pm; cost is $60 adults, $55 seniors 65 and older, $30 children 3 to 11, and free for 2 and younger. Reservations are a must; weight distribution is a factor. Check-in is at Neptune’s Gardens Gallery on Kukuihaele Road (www.neptunesgarden.net; 808/775-1343).

A Taste of the Hamakua Coast

When the Hamakua Sugar Company—the Big Island’s last sugar plantation—closed in 1996, it left a huge void in the local economy, transforming already shrinking villages into near ghost towns. But some residents turned to specialty crops that are now sought after by chefs throughout the islands. Hidden in the tall eucalyptus trees outside the old plantation community of Paauilo, the Hawaiian Vanilla Company (www.hawaiianvanilla.com; 808/776-1771) is the first U.S. farm to grow vanilla. Before you even enter the huge Vanilla Gallery, you will be embraced by the heavenly scent of vanilla. The farm hosts one of the most sensuous experiences on the island, the four-course Hawaiian Vanilla Luncheon ($42 for age 12 and up; $28 for kids 4–11), served weekdays from 12:30 to 2:30pm. The 45-minute Farm Tour ($25 for age 4 and up; free for kids 3 and under), including dessert and tastings, takes place weekdays at 1pm. Reservations required for luncheon or tour; the gallery and gift shop are open 10am to 3pm Monday–Saturday.

Co-key, Co-key: What Is That Noise?

That loud, chirping noise you hear after dark, especially on the eastern side of the Big Island, is the cry of the male coqui frog looking for a mate. A native of Puerto Rico, where the frogs are kept in check by snakes, the coqui frog came to Hawaii in some plant material, found no natural enemies, and spread quickly across the Big Island, concentrated on the Hilo side. (A handful have made it to Oahu, Maui, and Kauai, where they’ve been swiftly captured by state agriculture teams devoted to eradicating the invasive species.) A few frogs will sound like singing birds; a chorus of thousands can be deafening—and on Hawaii Island, they can reach densities of up to 10,000 an acre. Coqui frogs don’t like the cool weather of Waimea and Volcano as much, but anywhere else that’s lush and rural is likely to have large populations. Pack earplugs if you’re a light sleeper.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.