That sounds like it's going to be pretty full day.
There are some Native American pictographs on a rock at Blair Valley. You drive several miles up an easy sandy trail (2WD, I've seen BMW's in the parking area) then walk up about 1 mile along a well-marked trail to a large rock with pictographs. Follow the signs for the Pictographs, and the road and hiking trail are described in several guidebooks. We've had a few club runs out there over the last few years, look for references to Blair Valley in the Pictures section.
Here is a shot of the rock with someone in it for scale - in this case Mitch, who was translating the meaning of the symbols for us.
Also, on the way up to the Pictograph Trail there is another shorter hiking trail (about 1/4 mile) that leads to the site of an old Native American village. There are quite a few mortero holes in the rock, where they used to grind stuff up. There are also a few around the pictograph rock, probably used to grind up the pigment for the symbols.