Mt. Ka’ala is the highest peak on Oahu at 4,025 ft. As difficult as this sounds, a paved path will lead you up a third of the trail, while purple bottle caps guide your way throughout. You will first pass two water towers, a picnic table (stay on the right), and cross a dried up river bed. Watch out for steep inclines towards the top and lots of rope climbing. At the top is a nature preserve that will make you feel like you’ve landed on an unknown planet. Stay on the boardwalk to reach the satellite towers.