This happened when I was 15 years old.
My family and I lived in a small town that had very few stores. One Saturday my aunt wanted to take me to the nearest big city (Jackson, MI) to go shopping at a mall. We were both very excited to become again part of civilization. We spent the whole day there and around dusk decided it was time to start the hour long drive back home. It only takes two roads to get from Jackson to the town we lived in. The first road is an express way then you get off on a regular 2 lane road.
So we get on the express way and we're just jabbering away about all the things we bought and saw that day (on the express way mind you) when suddenly we both look around and I say to her, "Where are we?" She looked scared and said she didn't know and that she hadn't gotten off the express way, but we were on a small dirt road. We kept going straight for a while until we saw a building, we were going to ask for directions. The building was what looked to be a small country store and had two dirty overall and straw hat wearing men sitting on rocking chairs on the porch. They stared at us.
We turned around and headed back the way we had come. We were silent for a long time and just as suddenly as before we were on the express way. We looked behind us and it also was express way. We got off the express way and got on at the same ramp we originally took only this time we did not end up on that dirt road again. I can find no explanation for what happened. And it still freaks both my aunt and myself out.