This long dayhike or backpack is one of the best in the entire National Park, and is the closest you can get to the site of the former eruption, Pu’u ʻŌʻō. This hike starts with the beginning of the Pu’u Huluhulu trail. The Nāpau trail crosses vast oceans of new lava and skirts a few massive craters before entering a 150 year-old rainforest. After hiking in the rainforest for a bit, you abruptly come to the edge of Nāpau Crater, which provides the closest vantage possible to the former eruption site. If you’re lucky enough (or plan well enough) to do this hike on a clear day, you’ll have an amazing view. Those wishing to make a backpack out of this long hike can camp at the Nāpau Campground located at the end of the trail. Register for a camping permit and pay your fee at the Visitor Center or the Backcountry Office.

Trailhead: From the Park entrance, drive about 50 feet and turn south on Crater Rim Drive. Follow Crater Rim Drive to Chain of the Craters Road. On the Chain of the Craters road, find the Mauna Ulu parking area at the end of a short spur road that departs Chain of the Craters road between the 3 and 4 mile markers. The spur road dead-ends into a roundabout with a small parking area with a restroom. 

Hawai’i Volcanoes National Park Overview

Weather

Gear: This is a long hike in a big wilderness, so pack enough gear for a very long day hike. Bring extra water and food, and ensure you have appropriate raingear and some warm clothing because this entire hike is about 3000' above sea level.  

Hike: From the parking area, walk about 100 feet on pavement and turn left on the Pu’u Huluhulu trail. Sign in at the trail register. This portion of the trail is marked with numbered sites where you can learn about lava flows and the flora and fauna along the trail. You can find a trail guide near the trailhead for a few dollars donation or download it: Mauna Ulu Eruption Guide. Walk for 1 mile, following ahu (cairns), along pāhoehoe until you reach the trail intersection of the Nāpau Trail and the trail that leads to the summit of Pu’u Huluhulu. Pass Pu’u Huluhulu and enter a vast expanse of lava. The shield volcano to the south is Mauna Ulu, which erupted until 1974. Follow the changing path through this area set by cairns. Pulu FactoryAfter a stunning 2.2 miles of hiking across this wasteland, you’ll come to the edge of Makaopuhi Crater. This crater erupted in 1922, 1965, and 1972. The 500 year old double crater is the largest in the east rift zone. The trail here begins to skirt the crater and enters a dense and beautiful rainforest. Although this area seems like old growth, this area was covered by lava in 1840. Pass through the sometimes dense rainforest toward an old Pulu factory. Pulu is the felt-like substance in the trunks of the Hāpuʻu pulu ferns endemic to the island, and it has natural antibiotic properties. This factory processed pulu from 1851 – 1884, when the industry failed because pulu broke down into dust very rapidly in drier climates. From the first time you intersect Makaopuhi Crater, it’s another 2.5 miles to the edge of Nāpau Crater. The trail can be quite overgrown in the rainforest sections, but the right way to go is always obvious. At the end of the trail, you’ll abruptly find a steep overlook in the rainforest over Nāpau Crater onto Puʻu ʻŌʻō. It erupted constantly from 1983 to 2018. Be careful along the edge, and go no further. Return the way you came.