Wailua River To Secret Falls (An Adventure in 3 parts)   1) The Paddling Part Paddle 45 minutes up Hawaii’s largest navigable river until you run out of navigable river.  Leave your boat behind at the landing beach next to the trailhead.   2) The Walking Part Follow the trail along the riverbank through the jungle for 30 minutes until you arrive at Secret Falls. Much of the trail is a comfortable boardwalk. Some mild river crossing is involved. Who knew mango trees get so big?   3) The Lazing Part There’s a boulder for everyone.  Or swim in the natural pool at the foot of this 100 foot waterfall wonder.   (Then do it all backwards)