Home to nearly a million people, Oahu is the third-largest of the Hawaiian Islands and home to the state’s capital, Honolulu, which lies on the southeast coast.
With nearly 600 square miles of land, it’s among the largest islands in the United States.
It boasts nearly 230 miles of shoreline and is primarily comprised of two volcanic mountain ranges – the Wai’anae and Ko’olau.
Due to its heavy annual rainfall, the ranges and valley between them are covered with lush, green vegetation, and the island is home to a large number of waterfalls too.
It’s important to note that all untreated fresh water in Hawaii is possibly contaminated with the Leptospirosis bacteria, which makes it dangerous to swim in.
1. Manoa Falls
Conveniently located just a few miles from Honolulu and one of the island’s premier tourist destinations, Manoa Falls is one of the many amazing waterfalls in Oahu and is a great place to get your first taste of all the island has to offer.
Viewable from an easy trail less than two-mile roundtrip, you’ll be led through an enchanting forest of banyan trees and bamboo before you reach the main attraction.
The island is known for sporadic and sudden rain showers, which can make the trail a bit slick, so watch your step.
At trail’s end, you’ll be treated to a panoramic view of the 150-foot waterfall, but swimming in the pool at the bottom is discouraged because of the prevalence of dangerous organisms that reside there; stick to the hotel pool unless you’ve got plenty of room on your itinerary for a trip to the ER.
2. Upside-Down Waterfall
If standing on your head to see a waterfall the way it’s supposed to look sounds like a good idea, then the Upside-Down Waterfall should be on your to-do list.
Many of Oahu’s waterfalls are maddeningly remote, making them nearly impossible to get a good look at, except by helicopter.
One that can be seen easily from the Pali Highway, however, Upside-Down Waterfall has the strange distinction of being a waterfall where the water never really hits the ground, because as it descends, it’s buffeted by strong winds that disperse it before it has a chance to make contact.
The waterfall comes to life after a heavy rain, and though it can be seen from the road, there isn’t a safe place to stop to get a good look, so keep your camera at the ready.
3. Lulumahu Falls
If the term, ‘off the beaten path’ gets your heart pumping, then a trip to Lulumahu Falls may be a good idea.
You won’t run into hordes of noisy tourists, as this remote waterfall isn’t on most visitor’s itineraries.
You will, on the other hand, need to get a permit from the Hawaii Department of Forestry and Wildlife, because it’s located on state land near the Kaniakapupu Ruins where there are remnants of a former Hawaiian King’s summer home.
Though there are two trail entrances that’ll lead you to the falls, they’re not clearly marked and the hike won’t be an easy one. The easiest to find is at the end of Old Pali Road; once you’ve found it, the trail is sufficiently marked to get you to the falls in about an hour.
4. Likeke Falls
Though at 15-feet, Likeke Falls is modestly sized by Hawaiian waterfall standards, it’s a favorite with tourists due to the relative ease with which it’s viewed.
Located about 10 kilometers northeast of Honolulu, the trailhead is easily accessible and parking is free.
If you see other cars but are unsure of where the trailhead is, just hang around; it’s a favorite spot for locals to hike and they’ll be glad to show you the way.
Visitors have said that the red earth gets very slick during and after rain, so don’t wear those white Gucci loafers you’ve been saving for the trip.
Bring a few bottles of water, a raincoat, and a can of bug spray too, as the mosquitos can be overwhelming at certain times of the year.
5. Maunawili Falls
One of Oahu’s most easily accessible and therefore popular tourist sites is Maunawili Falls.
If at all possible, schedule your trip to the falls during the week to avoid the worst of the noisy crowds that tend to congregate here on the weekends.
The trailhead is an easy and scenic drive from Waikiki; once you get there, the roundtrip hike to the falls is less than three miles. The conditions of the trail can make the hike treacherous due to the slick, red mud which makes getting a secure foothold difficult, especially after rain.
If, however, you soldier through despite the hazards, you’ll be rewarded with a scenic 25-foot waterfall and beautiful views of the area’s lush fauna and surrounding mountains.
6. Jackass Ginger Pool Falls
With a name like Jackass Ginger, it must be one of the most amazing waterfalls in Oahu, right?
Located in Honolulu’s Nu’uanu neighborhood, Jackass Ginger Falls is a picturesque 10-foot tall waterfall and swimming hole popular with tourists and locals alike.
Rumor has it that generations ago, Hawaiian royalty relaxed nearby and plunged into its waters to get some relief from the heat.
It’s located on the Judd Memorial Trail, which is maintained by the state for its historical and tourism value.
It runs along the Nu’uanu Stream and is only about a half mile from the trailhead to the falls, although it can be hard to follow due to poor markings and overgrown vegetation. Despite the fall’s modest size, there’s a deep pool below suitable for swimming if you’re willing to dismiss the aforementioned health warning.
7. La’ie Falls
Officially, you’ll need a permit to hike the trail to La’ie Falls, so check that out before you make the hike.
The permits are available at the Hawaii Reserves, Inc. office in the shopping center in La’ie, though reports vary whether or not the permit is free or just inexpensive.
At just short of eight miles round trip, the trail isn’t for the very young, elderly or unfit, as it’s rocky and slippery – especially after rain. Depending on your physical abilities and motivation, the hike can take up to four hours and the falls are approximately 15 feet in height.
The surrounding vegetation and geology will make the trip a memorable if exhausting one.
8. Waimea Falls
Also known as Waihi Falls, whatever you call these falls, they’re some of the most accessible on Oahu. Their proximity to the botanical gardens and archaeological sites in the Waimea Valley make them a great place to visit on the same day as these other must-see sites.
There’s a small fee to enter the park, but the cost is minimal and goes to the non-profit organization that’s preserving these treasures.
Though the hike to the falls is nearly four miles, most of the journey is flat and paved and winds its way through the scenic gardens, so it’s a great place to take a leisurely stroll and enjoy all the area has to offer.
The falls are part of the Kamanui Stream and are a little less than 50 feet in height.
9. Kapena Falls
An easy drive from downtown Honolulu and located on the Kapena Falls Trail, the Kapena Falls offer great photo-ops for nature lovers and aspiring photographers.
Though the water is brownish-red from the red earth upstream, the pool below the fall’s 30-foot drop is clean and refreshing, according to those who decided to take a dip.
Car-size boulders and hanging vines give the area a primordial feel, which will keep you looking over your shoulder for long-extinct predatory dinosaurs that may be lurking in the shadows.
Due to its beautiful but ominous aura, it has been the location of choice for more than a few movies and TV shows, including, Lost.
10. Waikahalulu Falls
If like me, you thought that urban waterfalls didn’t really exist, then a trip to Waikahalulu Falls may change your mind.
Tucked into the Lili’uokalani Gardens in Honolulu’s busy urban center, the falls are just a tick over 10 feet tall.
The water slides over a wide rock crest before ending up in the idyllic pool below.
Though probably a bit more worn than it was in ancient times, it was purportedly a favorite spot of Hawaiian Queen Lili’uokalan, after who the gardens were named.
A recent re-planting has been initiated to restore the area to near-pristine condition in an attempt to reintroduce some native fauna that has become scarce.
The area is a great place for a picnic, or just to escape the hustle and bustle of the city, even if just for a few hours.
11. Hamama Falls
Another one of the amazing waterfalls in Oahu, Hamama Falls is found near Kane’ohe. They’re accessible by a relatively easy hike that’s around two miles each way.
You probably won’t find many crowds here, as Hamama Falls aren’t among the most popular falls on the island.
If you decide to make the hike, you won’t regret it, because the scenery surrounding the 40-foot waterfall is stunning. Since you may have the place nearly to yourself, it’s a great spot to read a book, make a sketch or just enjoy the serenity.
If a four-mile hike is a bit much, there’s an easy to find swimming area just a few minutes from the trailhead.
Remember that the trail is on state land, and technically a permit is required, but most visitors don’t bother.