I spent a lot of time researching which hike to do along the Napali Coast and decided to take the Kalalau Trail to Hanakapiai Falls. It's an 8-mile roundtrip trek and is absolutely worth doing. I consider myself an advanced hiker so it was a real treat to experience such a varied terrain -- not to mention extremely beautiful. It lived up to the hype of everything I read about it and more. When we reached the falls, I was reluctant to get in the water since it was very cold. But after that long journey, it felt like this was the reward I worked so hard for and slowly immersed myself in. Some tips: bring proper footwear (I wore light hiking shoes and swapped to water shoes when I'd cross over the streams, which became very useful especially swimming inside the waterfall), plenty of water, a towel if you intend to swim (which you should), a light wind breaker to keep warm after dipping in (this area is very shaded so I found it crucial when the winds were blowing, and I was so happy to have one since I didn't bring a towel), sunscreen, bug repellent, and some food to enjoy when you get there.