Coppertone and I spent most of this tour on a bus, but we did manage to get a short hike in here at the Haleakala Crater. The bus driver actually warned us about going up the Pa Ka'oao Trail from the crater visitor's center because of its unstable nature liability insurance for the tour operator, etc. We weren't going to spend 30-45 minutes sitting in the small visitors' center, so off we went.
The views from atop the conical mound were much better than from the center, so we're glad we took our lives in our own hands to make the trek. In truth, the path is marked by the park with no warning signs. Yes, there are some loose rocks around, but it was not terrible strenuous (other than the high altitude!) or dangerous.
We could see many more trails leading off into the distance, including within the crater itself. Hopefully the next time we're on Maui we'll have more free time to come and hike him rather than catch a fleeting glimpse.