Koko Crater is the hardest of Honolulu's hikes and the most rewarding view. The trail follows the tracks of a disused military incline railway up the inside of the crater wall — roughly 1,000 wooden railway ties acting as steps at gradients that reach 45 degrees near the summit. It is steep, relentless, and takes 45 to 90 minutes depending on fitness. The view from the top, 368 metres above the ocean, takes in the crater interior, Hanauma Bay, the Koolau mountains, and the eastern coast of Oahu.
The trail is most popular at sunrise, when determined hikers begin the ascent in headlamps to catch the dawn. It is exposed to the sun from mid-morning and gets very hot; go early and bring plenty of water. Located at the end of the Koko Crater Botanical Garden road in Hawaii Kai, about 30 minutes from Waikiki by car.