On US70 about half way between the main gate at Holloman AFB and the White Sands visitor center, on the north side of the road, is Holloman Lake, public access recreation area, where boondocking is allowed. The lake water is dangerous to come in contact with however.
Holloman has a visitor center that is outside the main gate, just turn in like you are headed to the security guard and then turn right. Never been there, found it on Google Maps, looks like it is worth a stop in in the area. If they allow you on base, which they may, about 3000 ft straight ahead from the security guards is a park on the right with about ten aircraft displayed, including a German Toronado strike aircraft.
Charles