An exotic landscape of dense rain forest surrounded by cliffs and known for its prominent lava formation.

Rising 1,214 feet (370 meters) from the valley floor is the rocky pinnacle known as 'Iao Needle. The lava formation covered in lush vegetation is the most recognizable landmark in 'Iao Valley State Park, and looks down on a valley floor of dense rain forest.
The needle is an extension of the West Maui Mountains, an extinct volcano. The last major eruption here was over 500,000 years ago.

Walk to the needle along the 'Iao Needle Lookout Trail and Ethnobotanical Loop. This is a half-mile (800-meter) paved trail that borders the 'Iao stream, starting at the parking area and restroom. The gradient is gentle enough for children, and there is a lookout point at the end of the trail. Bring plenty of insect repellant with you as clouds of mosquitos hover near pools of fresh water.

The best views of the needle from the valley floor come earlier in the day before the clouds arrive and obscure the peak. 'Iao means “cloud supreme,” and the park is the one of the wettest spots in Hawaii. On the way back, take the Ethnobotanical Loop to a small botanical garden featuring indigenous plants.

The park is a place of great local historical significance. It was here, in 1790, that King Kamehameha fought a savage battle against Maui’s army in his quest to unite Hawaii under one ruler. He won, but hundreds of warriors were slaughtered, and their bodies were said to dam the 'Iao River for a time.

'Iao Valley State Park is located at the end of 'Iao Valley Road (Highway 32), 3.1 miles (5 kilometers) west of Wailuku.