Oʻahu pillbox hikes are a thing in a way they really aren’t anywhere else in Hawaiʻi. Squat concrete observation bunkers, relics of the coastal defense buildout that followed the Pearl Harbor attack, sit perched along ridges all the way around the island. The army never had to use them. Eighty-plus years later they’ve become the destination of some of the most-photographed short hikes on the island: short enough to do before breakfast, high enough to give you a view that re-orients your whole sense of Oʻahu, and just gritty enough that the photo at the top is a small earned thing rather than something you drive up to.
Four of them are worth a visitor’s time. Two are popular enough to have parking problems and the occasional serious accident. Two are quieter, and one of those two is now my pick. Below is the field guide: what’s at the top of each trail, what the trailhead is actually like, and the small handful of safety and etiquette things that keep these hikes from going on the “closed by the state” list the way a few other beloved Oʻahu trails have.
If you’re here for sunrise specifically, our best sunrise hikes guide covers the dawn version of Lanikai Pillbox alongside the rest of the islands. This post is the broader pillbox-by-pillbox tour, sunrise, daytime, or evening.
