North Shore
Easy 4km round trip to two WWII military bunkers perched above the North Shore. The payoff is a front-row seat looking straight down on Pipeline and Sunset Beach — best place on the island to watch big-wave surfing in winter without being in danger. Allow 30 min to the first bunker, 10 more to the second.
No booking required. Free. Trailhead is across from Sunset Beach Elementary School — look for the yellow/orange "Mahalo" sign. Street parking along Kamehameha Hwy.
Best November–February when big surf is running. Go early before the hike gets crowded.