Round Trip Mileage: 2.75 miles
Elevation Gain: 300 feet
The Kaumana Trail is a short hike off of the Saddle Road that offers a great way to explore the lava and rainforest in the area. If the weather is clear, you get big views of Mauna Kea and Mauna Loa. This trail, part of the state's Nā Ala Hele system, is a remnant of the old Puʻu ʻŌʻō Horse trail that once carried supplies and cattle from Hilo to the defunct Puʻu ʻŌʻō Ranch high on the slopes of Mauna Kea. (The name of this ranch has nothing to do with the site of the current eruption of Kīlauea, also called Puʻu ʻŌʻō). Kaumana is a much shorter segment of the old ranch trail than the Puʻu ʻŌʻō Trail in the same vicinity. It follows an 1855 lava flow from Mauna Loa through and area with several kīpuka, which are areas of old-growth forest spared between newer lava flows. These islands of old-growth forest provide a unique habitat for endemic birds and plants. The Kaumana Trail is always open. Hunting is allowed, so you may want some bright clothing for the hike.
Trailheads: From either side of the island, drive to Hwy. 200, the Saddle Road that bisects Mauna Loa and Mauna Kea. There are two trailheads to choose from. Both are between mile markers 18 and 20.
Western Trailhead: This parking area has a large paved pullout on the side of the road. It is located between mile markers 19 and 20, closer to mile marker 20. The trail has a brown sign with yellow lettering from the state Nā Ala Hele system.
Eastern Trailhead: This parking area is big enough for 3-4 cars and has a gravel parking area off the main road. It is located between the 18 and 19 mile markers on Hwy. 200. It is also marked with a brown sign with yellow lettering from the state Nā Ala Hele system.
Gear: This hike is near an elevation of 5000' above sea level off of the Saddle Road, so it's much cooler than coastal destinations. Bring your raingear. You'll appreciate sturdy shoes or boots on the rough trail.
Hike: From either the western or eastern trailhead, spot a brown and yellow Nā Ala Hele sign marking the beginning of the trail. The Kaumana Trail is well-defined because it was an old horse trail. There are several ahu (cairns) to mark the way. The trail veers very close to several kīpuka where old-growth forest avoided newer lava flows. They contain many species of endemic birds. It's possible to explore them, but footing is very uncertain and they can be quite dense. When you hit the other end of the trail, return the way you came.