The trails of Oahu cover a full spectrum of environments: desert walks through cactus, slippery paths through bamboo-filled rain forest, and scrambling rock climbs up ancient volcanic calderas. The only thing you won't find is an overnighter, as even the longest of hikes won't take you more than half a day. In addition to being short in length, many of the prime hikes are within 10 minutes of downtown Waikiki, meaning that you won't have to spend your whole day getting back to nature.

Hawaii State Department of Land and Natural Resources. Go to the website for information on all major hiking trails on Oahu. You can also obtain camping permits for state parks here. 1151 Punchbowl St., Room 310, Honolulu, Hawaii, 96813. 808/587–0300; dlnr.hawaii.gov/dsp/hiking/oahu.

Na Ala Hele Trails and Access. Contact the Na Ala Hele ("Trails to Go On") folks for a free hiking-safety guide and trail information. The interactive website has maps and information about the current status of trails on all of the Islands. You can also stop in their office for free printed maps and information. 1151 Punchbowl St., Room 325, Downtown, Honolulu, Hawaii, 96813. 808/587–0166; hawaiitrails.hawaii.gov.

Best Spots

Diamond Head Crater. Every vacation has requirements that must be fulfilled, so that when your neighbors ask, you can say, "Yeah, did it." Climbing Diamond Head is high on that list of things to do on Oahu. It's a moderately easy hike if you're in good physical condition, but be prepared to climb many stairs along the way. Also be sure to bring a water bottle, because it's hot and dry. Only a mile up, a clearly marked trail with handrails scales the inside of this extinct volcano. At the top, the fabled final 99 steps take you up to the pillbox overlooking the Pacific Ocean and Honolulu. It's a breathtaking view and a lot cheaper than taking a helicopter ride for the same photo op. Last entry for hikers is 4:30 pm. Diamond Head Rd. at 18th Ave., Diamond Head, Honolulu, Hawaii, 96815. 808/587–0300; dlnr.hawaii.gov/dsp/parks/oahu/diamond-head-state-monument. $1 per person, $5 to park. Daily 6–6.

Kaena Point Trail. Kaena Point is one of the island’s last easily accessible pockets of nature left largely untouched. For more than a quarter century, the state has protected nearly 60 acres of land at the point, first as a nature preserve and, more recently, as an ecosystem restoration project for endangered and protected coastal plants and seabirds. The uneven 5-mile trail around the point can be entered from two locations—Keawaula Beach (aka Yokohama Bay) at the end of Farrington Highway on Oahu’s western coastline, or Mokuleia at the same highway’s northern coast endpoint. It's a rugged coastline hike without much shade, so bring lots of water and sunscreen (or better yet, start early!). Keep a lookout for the Laysan albatrosses; these enormous birds have recently returned to the area. Don't be surprised if they come in for a closer look at you, too. 81-780 Farrington Hwy., Waianae, Hawaii, 96792. dlnr.hawaii.gov/dsp/hiking/oahu/kaena-point-trail.

Makapuu Lighthouse Trail. For the less adventurous hiker and anyone looking for a great view, this paved trail that runs up the side of Makapuu Point in Southeast Oahu fits the bill. Early on, the trail is surrounded by lava rock but, as you ascend, foliage—the tiny white koa haole flower, the cream-tinged spikes of the kiawe, and, if you go early enough, the stunning night-blooming cereus—begins taking over the barren rock. At the easternmost tip of Oahu, where the island divides the sea, this trail gives you a spectacular view of the cobalt ocean meeting the land in a cacophony of white caps. To the south are several tide pools and the lighthouse, while the eastern view looks down upon Manana (Rabbit Island) and Kaohikaipu islets, two bird sanctuaries just off the coast. The 2-mile round-trip hike is a great break on a circle-island trip. From late December to early May, this is a great perch to see migrating humpback whales. Be sure not to leave valuables in your car, as break-ins, even in the parking lot, are common. Makapuu Lighthouse Rd., Makapuu, Honolulu, Hawaii, 96825. dlnr.hawaii.gov/dsp/hiking/oahu/makapuu-point-lighthouse-trail.

Manoa Falls Trail. Travel up into the valley beyond Honolulu to make the Manoa Falls hike. Though only a mile long, this well-trafficked path, visited by an estimated 100,000 hikers a year, passes through so many different ecosystems that you feel as if you're in an arboretum—and you're not far off. (The beautiful Lyon Arboretum is right near the trailhead, if you want to make another stop.) Walk among the elephant ear ape plants, ruddy fir trees, and a bamboo forest straight out of China. At the top is a 150-foot waterfall, which can be an impressive cascade or, if rain has been sparse, little more than a trickle. This hike is more about the journey than the destination; make sure you bring some mosquito repellent because they grow 'em big up here. 3998 Manoa Rd., Manoa, Honolulu, Hawaii, 96822. www.hawaiitrails.org/trails/#/trail/manoa-falls-trail/225.

Maunawili Falls. Want to find a waterfall that you can actually swim in? Then Maunawili Falls is your trip. In fact, even if you don't want to get wet, you're going to have to cross Maunawili Stream several times to get to the falls, and the route is pretty muddy. Along the 1½-mile trek enjoy the ginger, vines, and heliconia before greeting fern-shrouded falls that are made for swimming. The water is not the clearest, but it's cool and refreshing after battling the bugs to get here. On weekends the trail can be very crowded. Prepare to park far from trailhead as regulations are strictly enforced. Be sure to bring mosquito repellant. Walking sticks are helpful—if you don't have any, use the loaner sticks often left by hikers at the trailhead. 1221 Kelewina St., Kailua, Hawaii, 96734.

Trails at Turtle Bay Resort. When on the North Shore, check out the Turtle Bay Resort, which has more than 12 miles of trails and oceanside pathways. You can pick up a map of the resort property, which includes trail and coastal jogging paths. 57-091 Kamehameha Hwy., Kahuku, Hawaii, 96731. 808/293–8811; www.turtlebayresort.com.

Aiea Loop Trail. This 4.8-mile loop begins and ends in the Keaiwa Heiau State Recreation Area, running along the ridge on the west side of Halawa Valley. It's a fairly easy hike that lasts about 2½ to 3 hours and brings many rewards, including views of the southern coastline of Oahu from Pearl Harbor and the Waianae Range to Honolulu and Diamond Head. Foresters replanted this area with various trees in the 1920s, so scents of lemon eucalyptus, pine, koa, and other trees enhance the trek. There's ample parking near the trailhed, close to restrooms and a picnic pavilion. Aeia District Park, 99-350 Aiea Heights Dr., Aiea, Hawaii, 96701. 808/587--0300; dlnr.hawaii.gov/dsp/hiking/oahu/aiea-loop-trail.

Going with a Guide

Hawaii Nature Center. A good choice for families, the center in upper Makiki Valley conducts a number of programs for both adults and children. There are guided hikes into tropical settings that reveal hidden waterfalls and protected forest reserves. They don't run tours every day, so it's a good idea to get advance reservations. 2131 Makiki Heights Dr., Makiki Heights, Honolulu, Hawaii, 96822. 808/955–0100; www.hawaiinaturecenter.org.

Oahu Nature Tours. Guides explain the native flora and fauna and history that are your companions on their various walking and hiking tours on Oahu. This outfitter offers tours to the North Shore, Diamond Head, and Windward Oahu. The company also offers much more expensive private birding tours, perfect for those interested in spotting one of Hawaii's native honeycreepers. Tours include pickup at centralized Waikiki locations and are discounted if booked online in advance. 808/924–2473; www.oahunaturetours.com. From $35.

North Shore Eco Tours. Native Hawaiians own and operate this business, the only one allowed to lead guided small-group adventures in private conservation lands. Options range from 2-mile and 3.5-mile roundtrip hikes to pools and waterfalls (lunch included) to an off-road expedition in all-terrain vehicles. Hiking adventures begin at a pickup point in Haleiwa town at North Shore Marketplace; off-road tours begin in Waimea Valley. North Shore Marketplace, 56-250 Kamehameha Hwy., Haleiwa, Hawaii, 96712. 877/521–4453; www.northshoreecotours.com. From $95.