If you’ve seen just one photograph of Maui's lush interior, odds are it was of the magnificently phallic 2250ft ʻIao Needle, the green pinnacle that provides the focal point for ʻIao Valley State Monument. Visitors can climb the 133 steps to a viewing platform with stunning views of the valley and Wailuku. The walk takes 30 minutes round-trip. On the way up, take the left fork for a quick detour to a paved loop through a tropical garden.
The Hawaiian garden provides a good vantage point to snap a picture of the ʻIao Needle. Then you'll reach a bridge crossing the 'Iao Stream – you may see locals jumping from it, but don't even try: it's dangerous. Those looking for a paddle can continue to another lefthand loop, where the river rushes slower and pools provide a good opportunity to cool off. Check the conditions before you dip, as these waters are subject to flash floods.
At the end of the marked pathway there's a prominent petroglyph of a stick man at the base of a big boulder (usually with offerings wrapped in leaves at the bottom of it). Look out for other petroglyphs along the way. Hundreds of years ago waters in this area helped create the largest irrigated agricultural system in Maui.
The park is 3 miles west of central Wailuku.