5Kalalau Trail, Hawaii, USA
The Kalalau Trail on the island of Kauai is one of the most challenging and dangerous hikes in the United States. This 22-mile round trip hike along the rugged Napali Coast tests both your physical strength and your nerves. The trail features steep cliffs, narrow paths, and slippery, uneven terrain, with sheer drops into the ocean below. The hike also requires crossing swift rivers and climbing up and down steep ridges. The physical demands of the Kalalau Trail are matched by the mental challenge of overcoming fear and staying focused on the treacherous terrain. Those who complete the trail are rewarded with stunning views of the turquoise waters and pristine beaches of the Napali Coast.