It was dark and clear below 2000 ft.As I was driving east on Hwy 37, past Skaggs Island, about 3-5 miles west of Vallejo, I saw two bright, white lights in the sky.At first, they appeared to be two landing lights from a larger airplane. I didn't pay too much attention to them, I just noted that it looked like an airplane, going in the same general direction as a "right downwind" for runway 24 at Napa Airport (KAPC). If it was a jet in the pattern, they'd be at ~1500 ft - and that's about what it looked like.I did start to notice that the "airplane" seemed to be "downwind" longer than normal, as it didn't turn right, to base, as it should have done - so, I started watching it more closely.Maybe it was a helicopter? But, a helicopter doesn't have widely spaced "landing lights". Maybe it was a helicopter with an advertising grid below, with 2 large lights? It seemed odd to me - and since I'd never seen a helicopter with a lighted advertising display, that would have to been pointed towards me so that the "directional" landing lights would stay a brightly white, from my viewpoint.Then, oddly, the two lights, that were level, seemed to bank and turn left (to my right, as it seemed to be heading towards me).What was odd, is that the two lights, didn't change in intensity."Landing lights", are "directional". If they aren't pointed at you, they, basically, go out.I'm a licensed pilot with quite a bit of night flying experience - and being based up north of San Francisco Airport, you can watch the landing lights of the passenger jets take off at night and watch them wink out as the jet makes it's eastward turn after takeoff.So, when this "thing's" right side light seemed to drop, and it seemed to turn "left" (my right), back towards Vallejo, it really stood out that the 2 lights didn't change in intensity at all. That would infer a non-directional light - and that wouldn't be on an airplane - as a non-directional light that bright, would blind the pilot's vision. Then, as it seemed to still be at about 1000-1500 ft, I saw a string of 7-8 dimmer lights tying the two bright light together.What was odd, and different from my first impression, was that the right side bright light stayed ~30 degrees lower than the upper left light (as if "it" was still banking) - but, the two lights stayed offset and the pair of bright lights (and the 7-8 dimmer lights connecting them) began obviously traveling east, at, I'd guess, at 40-50 mph. (as in def not 10-20 and def not 60-70) It wasn't turning anymore, it was traveling east over Hwy 80 up the Auto Mall "valley" - still with the two lights offset in height.I'd been watching it over the Napa River Bridge, through Vallejo (on 37), past 6 Flags Amusement park.I lost sight of it while taking the 37 / 80 west offramp. behind the overpass. I caught a brief glance of it looking backwards on 80 - Then I couldn't see the 7-8 dimmer lights between the 2 bright lights, but traffic was a bit hectic there.I took the first offramp and doubled back on Admiral Callaghan, I couldn't see it, but caught a momentary glimpse of a lighted spot 1000 to 1500 ft up on the valley ridge, right about at the Target store shopping center.I'd guess that it was 80% to 90% of the way to the top of the hills (I could see the outline of the ridgeline). The lighted spot was reflected light, and I couldn't see any particular point of light, just a very brightly lighted area 50 to 100 ft wide up near the ridge.I lost direct line of sight behind the auto dealers and when I got to the top of Admiral Callaghan, I couldn't see the light on the hill anymore.I went down to Auto Mall Parkway, turned right and kept looking up to find the lights again.Nothing.In recreating my initial view, what I first had thought was "downwind" on Rwy 24 at KAPC, was wrong. The lights were over the northern edges of the town of Vallejo, a few miles south of the airport, about inline with the Napa / Solono county borders.I'm 100% sure of the 2 non-directional lights, the 7-8 dimmer lights and the slow speed, the altitude and the light on the hillside.Duration of observation, about 10 minutes.