Oahu: 350-acre Diamond Head crater. Incredible panoramas of Honolulu that you will not find anywhere else. Easy hike; the very much beaten paths is easy enough for kids and the elderly, lengthy staircases (75 steps and 99 steps) and claustrophobia-inducing 225-ft tunnel to the top may be a challenge for the faint of heart. Make it to the top & have plenty of gorgeous photos to prove you’ve been to Hawaii. Open 6am-6pm $1 ($5 a car); get there early to avoid the crowds and heat of the sun.