A short hike off of Nu'uanu Pali Drive leads to a rather quaint and popular swimming hole known as Jackass Ginger Pool. Originally named Kahuailanawai, or tranquil water, the pool was renamed after a donkey that lived in the area nearly a hundred years ago, as well as the plentiful ginger plants that line the river side. Jackass Ginger Pool is a perfect place to take a dip or cannonball from the higher rocks into the deep and often murky water.
The pool is roughly a half-mile along the Judd Trail, although for first-time visitors, the way may not be completely obvious. From the road, enter the trailhead clearing with signage for the Judd Trail. Walk along the right bank of the river until the trail reaches a crossing. After the river crossing you'll find a junction before the bamboo forest; the right trail leads more directly to the pools. As the trail begins to ascend, hikers will begin to hear the sounds of rushing water. Follow a small switchback down to the now visible pool. Alternatively, a more direct route would be to follow along the river bank after the first crossing and junction. This way is a bit more scenic, less steep, and affords scenic views of some other small cascades and pools along the way.
At Jackass Ginger Pool, the rather uninspiring waterfall is a good place to bask in the cool river as the sun bathes the dark rocks. People are often seen leaping from the highest point (between 6 and 8 feet), clearing the rocks below, or sliding down the smooth flume on their bottoms. Given its short distance from the road and its relatively tame hydrodynamics, Jackass Ginger Pool is family friendly.
Street parking is available in dirt pullouts along Nu'uanu Pali Drive, just a short drive from downtown Honolulu. Start early, especially on fair-weather weekends, to avoid the crowds.
Swimming holes and cliff jumping can be extremely dangerous and unpredictable outdoor activities that pose significant risks regarding personal safety. Changing water levels, unseen rocks, and river bottoms that have shifted with currents and seasonal weather can turn a well-known jumping area into a serious hazard. Prior to engaging in these activities, extensively scout the current conditions, and understand the risks involved with serious injury and the logistical challenges of evacuation from the water so you can make safe decisions.