O'ahu's central plain is a patchwork of old towns and new residential developments, military bases, farms, ranches, and shopping malls, with a few visit-worthy attractions and historic sites scattered about. Central O'ahu encompasses the Moanalua Valley, residential Pearl City, and the old plantation town of Wahiawa, on the uplands half-way to the North Shore. Sights are reached by the H1 and H2 freeways.
West (or Leeward) O'ahu has the island's fledgling "second city" -- the planned community of Kapolei, where the government hopes to attract enough jobs to lighten inbound traffic to downtown Honolulu -- then continues on past a far-flung resort to the Hawaiian communities of Nanakuli and Wai'anae, to the beach and the end of the road at Keawe'ula, a.k.a. Yokohama Bay. West O'ahu begins at folksy Waipahu and continues past Makakilo and Kapolei on H1 and Highway 93, Farrington Highway.
A couple of cautions as you head to the leeward side: Highway 93 is a narrow, winding two-lane notorious for accidents. There's an abrupt transition from freeway to highway at Kapolei, and by the time you reach Nanakuli, it's a country road, so slow down. Car break-ins and beach thefts are common so have a care.
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