While Akaka Falls is the most well known waterfall on the Big Island of Hawaii, Rainbow Falls is a must see as well and a favorite of many locals.
Rainbow Falls is conveniently located in Hilo on the eastern side of the Big Island and is just a short walk from where parking is to view the falls. While Akaka Falls is over 422 ft and Rainbow Falls is only 80 feet the easy access as well as closer proximity you can get to Rainbow Falls make it a favorite of many. Rainbow Falls has two designed viewpoints. One is just a short walk from the parking lot. The other is if you head up some rather steep stairs to a higher viewpoint. One viewpoint is head on while the other is looking down upon the falls.
Rainbow Falls got its name since if you are there early enough in the morning you can get not only pictures of the waterfall, but also of nearby rainbows. This makes for some spectacular photographs. How the falls look is based on the amount of rainfall upstream. If there is a lot of rain, they can be roaring and if it has not rained in a few days you may be unfortunate to not even see a waterfall. If you are unfamiliar with Hilo, it is known the be the wet part of the island so it is likely that you will get to see a waterfall.
While the main waterfall where you park by is spectacular there are a lot of other beautiful areas of the falls if you have time to walk around the area. Many spots are not too accessible, but you can catch some nice glimpses through trees in some areas.
There are not too many parking stalls so you may have to wait a few minutes for other visitors to leave, but typically not too long since the waterfall is just steps away from the parking lot. There are also restrooms located just off of the parking lot.
If you are traveling from Waikoloa Beach Resort or any of the resorts on the Kohala Coast, it is highly recommended to take the northern route and stop at Akaka Falls on your way over there. The other alternative is to drive across the island and then take the norther route back, but overall the best pictures of the waterfalls will be taken in the morning so it is best to take the northern route so that you can stop off at both of them in the morning.