A hike up Diamond Head, a snorkel at Hanauma Bay, and a trip to Pearl Harbor require advanced reservations. See links in the post.

An easy adventure close to Waikiki is a hike up to Manoa Falls in a nearby valley.

The Koko Crater (or Koko Head) hike outside Honolulu, Hawaii is one of Oahu’s most popular hikes, and for good reason.