I was on vacation in Greece visiting friends and we were coming back from a small village in the mountains. As we drove, I asked my friends to stop numerous times to get photos of the incredible scenery. During one of the stops, we noticed strange lights moving around in the mountain valley. At first they were faint, but then appeared to zoom down into the valley before making a sharp left hand turn and shooting up. They hovered for a moment and appeared to be four balls of light and then they disappeared. We continued to drive and a short while later, I noticed a very faint trainge shape of lights in the daytime sky. I also took a photo of this.