Mauka on Highway 56, right around mile marker 6, you'll cross over Wailua River. If you're heading north, make sure you're in the left lane as the right splits off onto its own unique little bridge. You'll be looking for Kuamo'o Road (Highway 580) on the mauka side of the highway. Head up Kuamo'o Road until you see a pullout for Opaeka'a Falls on your right, shortly before the second mile marker. From this overlook, you can get a spectacular view of 150+ foot Opaeka'a Falls. The falls are at their best in full sunlight (late morning usually). So if you visit on a cloudy day, definitely try to return at a sunnier hour. Best of all, the falls are flowing year round. You're always certain to see it in action.
If you're wondering about the origin of the name Opaeka'a, it dates back to days when shrimp roamed the river and were seen rolling in the turbulent waters at the base of the falls. "Opae" is the Hawaiian word for "shrimp," and "ka'a" means "rolling." You may hear about a "hidden" trail to the falls that begins beyond the overlook, right around the two mile marker past the guardrail. We do and have always advised against this trail, mainly because you have to cross a fairly deep stream, walk down a steep hill, and then get out again. The trail is supposedly all on state owned land, but it is not maintained. (January 2007 Update) It's unfortunately this warning (from us and others) did not go headed by two visitors. In December 2006 two women died trying to take this hike; falling from near the top of this falls. The trail has been closed indefinitely. Please make note that this trail has nothing to do with the overlook mentioned above, and that the overlook is perfectly safe for all viewers. While not at all related to the fall themselves, just across the road from the falls overlook is another lookout over the Wailua River Valley. From this overlook you can get a good look at where Raiders of the Lost Ark was filmed, along with other big-name movies like "Jurassic Park" and "Outbreak." If you look to the right you can also get a good look at Kamokila Hawaiian Village.