Right before mile marker 9 on Highway 377, mauka side, you'll see the turn off for Waipoli Road. Waipoli Road includes several switch backs up the side of Haleakala to Polipoli Springs State Park, an infrequently visited but very beautiful state park on Maui.
Polipoli Springs State Park is located around 6,200 feet above sea level in the Kula Forest Reserve and encompasses nearly ten-acres of recreational area. This Upcountry park offers amazing views of both Maui below and the neighboring islands of Lana'i and Kaho'olawe. The towering trees, mature forest of redwoods, and other exotic native vegetation species such as plum, cypress, sugi, and ash are the highlights of the park. Several trails are also available.
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Since the road is only partially paved, and the rest merely graded dirt and gravel, it is recommended mostly for 4-wheel drive vehicles. However the first part of the drive should be quite accessible and you can walk the rest of the way if you're feeling up to a hiking challenge. A light jacket might also be a good idea as it can become quite chilly. If you decide to skip this stop, you'll soon find yourself back at the southern junction of Highway 37/377. Poli Poli Springs is 9.7 miles west of Kula Botanical Gardens entrance is Waipoli Road off Kekaulike Avenue (Highway 377). The park is located along this road before Keokea. The road is only partially paved - the rest is merely graded dirt and gravel.