The island of Maui is dominated by Haleakalā, a volcano that stands at over 10,000 feet above sea level. On your way driving up the long series of switchbacks, there are a couple of places to pull off the road and catch a glimpse of the crater.
At the Leleiwi Overlook, there is a quarter-mile hiking path that leads to a sturdy windbreak. From there, you can look down into a huge depression containing cinder cones and ancient lava flows that are frozen in time. What may look like a crater is actually an erosional valley formed by wind and water carrying rock and soil away from the volcano's summit.
Along the path you'll see plants that are unique to this volcanic ecosystem. Members of the pea, geranium and coffee families live along the trail to the overlook. While their flowers, leaves and seeds resemble their mainland relatives, these plants are especially adapted to life on the volcano.
Remember to bring a jacket and a warm layer on this short hike. You are nearly at 9,000 feet of elevation. Air temperatures are considerably colder here than on the beaches far below, and the constant wind makes the air feel even colder.