It’s Diamond Head, a crater that’s been around for about 300,000 years, and, well, if you’re on Oahu, you really do have to explore it — that is, unless you have a young child, in which case you might not want to risk it. Climbing the 0.8 miles up is steep and strenuous but totally doable and safe, but you don’t want to end up carrying more than just yourself up and down, if you know what I mean. The views from this unique hike are phenomenal, but the trail and stairs that make up a portion of the trail can get crowded.
Diamond Head State Monument
Diamond Head Road at 18th Street, Honolulu, 96815, HI