I'm not sure how to classify this story, could be paranormal, could be variables that I hadn't noticed at the time, but who knows.
Myself and two of my buddies went up to Sherkston Beach in Canada a few years ago, where my other buddy has a cottage. On the drive up, he mentions that there's this cool castle-type mansion being built down this gravel road off in the distance. We were interested at the time so we went down the gravel road to check it out. The road is about a mile long with no streets coming off in between the two main roads that it connects, and there was tall grass and trees on either side of the narrow road. So anyways, were driving down and we see 2 guys and 2 girls sitting on the hood of what looked like, a perfectly conditioned hot red muscle car from probably the 60s or 70s (I'm not much of a car guy) on the side of the gravel road. They seemed very friendly and waved to us as we maneuvered past where they were parked. They had an older looking camera and were taking pictures of each other on the car. We didn't think anything of it at the time, so we pass them stop and check out the immense mansion and then turn around and start heading back the way we came. We had to pass their car again to get back to the main road, so they waved to us again, as we passed. I'm about 20-30 seconds down the road, when I look in my rearview mirror and notice that the car is no longer there. There were only two ways off that street and I don't think there was any way they could've driven over half a mile in less than a 30 seconds without me seeing them or any dust or dirt from the road being kicked up.
I'm still not too sure what to make of the experience, but all I can say is that I can't explain how they disappeared so fast.