Late at night on July 14/15, 1996 at around 2 or 3 in the morning, I was driving with a relative on HWY 90 between Del Rio and Alpine. We were in the general area of Langtry, a ghost town, when we saw large circles of light on the hillsides, as though a floodlight or spotlight were shining down on them. We thought surely a helicopter was doing it, but the lights didn't shake or vibrate slightly as they would if it were a helicopter, but moved smoothly. We also could hear no sound whatsoever, and it was very much an aerial source, this couldn't have been done from the below the hills. There was nothing in the air that we could see, though. There was also no ground source. This is very confusing and bewildering as this area is also not easily wired for that kind of electricity, it is practically wilderness for a couple of hours (driving) in either direction. This was on the north side of the road, btw. About a mile or few from this, there is a campsite on the river, but not on this side of the road. This is also quite a deserted road at this time of night. I can also think of no reason for anyone to want to shine lights on these hillsides at night. That is very confusing. I know it is far too late to investigate this, but I thought perhaps if someone had reported something else similar or strange in that area, my story might contribute to the information they put forth. To clarify, these weren't Marfa type lights, this is the light you see on the ground when you shine light on it, like through a flashlight, but much larger - like a spot light. The lights did move, they weren't stationary as with a floodlight.