It's only about 0.6 miles to the petroglyphs. There is very little vegetations so you are totally exposed to both the sun and the sun beating off the rocks. The trail is up and down over relatively smooth lava. You definitely won't get a wheelchair up the trail. The path is reasonably well marked and once you get to the petroglyphs, they are beautifully preserved. Don't follow the suggestions of the other reviews that say get off the trail and look at the others. The point is to preserve them, not trek all over them. Keep your eyes open on the path out, as there are plenty to see there also.