This hike is probably the easiest in all of Hawaii (and in the U.S. in general), as long as you don’t go off the designated trail. It’s only about 1.5 miles. You’ll pass by steam vents to reach Mauna Loa and see the beautiful Halema’uma’u Crater and Kilauea Caldera. The (even) easier trek is the Earthquake Trail. You will walk on a paved road and see native plants, trees and birds, as well as severe earth cracks from the 1983 earthquake with a 6.7 magnitude.