What is the creepiest, most unexplained thing you have ever experienced?

I went for a late night drive down the coast outside of San Francisco one night to unwind a bit. I was the only car on the road for miles, and I pulled off at my favorite spot to look at the stars. I'm on top of a cliff about 100 feet high that has a steep walkable path down to the beach and is covered in bushes and other smaller plants. The path is steep enough that there are ropes that have been tied to help people get back up; it's no easy task.

Everything is dead silent and I'm enjoying the view when I see some of the bushes down below rustle. Thinking it was an onshore breeze that I couldn't feel, I thought nothing of it. All of a sudden, the bushes are violently being pushed around in a very specific place and I see something moving toward me far quicker than any human could possibly move. Something is coming up the cliff at me and fast.

I immediately bolt for my car. It was a convertible and the top was down, so I jumped over the door and had somehow pulled my keys out on the run back. I started it and dumped the clutch, barely getting enough traction on the sand to move until I hit the pavement and I was gone. I scanned my rearviews looking for anything, but saw nothing at all.

The scariest part was I could hear it scampering across the sand behind me as I started my car. It was only a few feet behind me. It scaled at least 75 feet of cliff in the time it took me to run 15 feet. I have no idea what in the hell that thing was to this day, but I'll be damned if I'm going back there on a dark night.

/r/AskReddit Thread