We went in late April on a whim and enjoyed near perfect temperatures, as well as free admission. As others have noted, they don't allow food or gum, only water. They recommend carrying extra water and stuff, but it's a very short, easy hike with only one small section of elevation gain. The trail is well marked and the archeological site is pretty well preserved. The volunteers do a nice job of giving interpretations along the trail, and if you ask, they'll tell you some good stories about the burn scar as well. Definitely worth a small detour, though a quick stop at the visitor center doesn't hurt either. Be aware of the limited hours of opening as well.