Waipio Valley is located in the Hamakua District of the Big Island of Hawaii. Waipi’o means “curved water” in the Hawaiian language. It was the capital and permanent residence of many early Hawaiian ali’i (kings) up until the time of King ‘Umi.

Located at 20 7 11 N 155 35 36 W, the valley floor at sea level is almost 2,000 ft (610 m) below the surrounding terrain. A steep road leads down into the valley from a lookout point located on the top of the southern wall of the valley. The road gains 800 vertical feet (243.84 m) in 0.6 miles (0.9 km) at a 25% average grade, with steeper grades in sections.

This is a paved public road but it is open only to 4 wheel drive vehicles. If classified as a road, it would be the steepest road of its length in the United States and possibly the world. The shore line in the valley is a black sand beach, popular with surfers. Several large waterfalls fall into the valley to feed the river which flows from the foot of the largest falls at the back of the valley out to the ocean.

The valley was the site of the final scene in the 1995 sci-fi film Waterworld, at which the main characters found dry land. [Source: Wikipedia]