Go in the morning, around 9 or 10am, just as the sun comes over the mango trees, to see Rainbow Falls, or Waianuenue, at its best. Part of Wailuku River State Park, the 80-foot falls (which can be slender in times of drought) spill into a big round natural pool surrounded by wild ginger. If you’re lucky, you’ll catch the rainbow created in the falls’ mist. According to legend, Hina, the mother of Maui, once lived in the cave behind the falls. Swimming in the pool is not allowed, but you can follow a trail left through the trees to the top of the falls (watch your step). About 2 miles upriver, the Wailuku also passes through a picturesque series of hexagonal pools nicknamed Boiling Pots, although the often-bubbling water is actually cool. From the parking lot at Rainbow Falls, take Rainbow Drive to Waianuenue Avenue, and follow it another 1 3/4 miles west to a right on Peepee Falls Road, named for the falls (pronounced “peh-eh-peh-eh”) that feed the Boiling Pots. There’s a parking lot at the end of the road. It’s a local swimming and diving hole, but both activities are risky—waters can rise quickly after a cloudburst.