Koko Crater Arch is a popular scenic vista accessible from the Halona Blow Hole Lookout parking lot. This short and steep hike climbs the side of the volcanic crater to the rim, passing a natural stone arch feature for which the hike is named. Views along the way are impressive, and the neighboring islands of Maui and Lana'i are visible on clear days. In the winter, whales can be spotted off the coast.
As you reach the arch, use careful foot placement on the steeper slabs of stone. The arch is a good place for inexperienced hikers to turn around; the section above the arch is extremely inclined as you gain the ridgeline. For those who are comfortable, proceed up toward the ridge by traversing the natural arch. Use the carved out footholds and bolts as guidance. Be sure to proceed slowly and carefully as this slick slab of rock is dangerous. Do not attempt in high wind or rain. Be aware that a sudden rainstorm can make the descent slippery and unstable.
From above the arch, the steep ascent follows a narrow path that forks near the top; either way will bring you the ridgeline. At the ridge you will be rewarded with an amazing view into the Koko Head Crater and of the surrounding coastline, including Hanauma Bay, Cockroach Cove, and the Halona Blow Hole. Hikers can return the way they came, down the steep flanks of the crater, or along the Koko Crater Rim Trail toward the summit and the Koko Head Stairs. Be sure to come prepared with plenty of water, sunscreen, and shoes with good traction.