Went to Laurel Caverns (east of Uniontown Pa.) with my wife yesterday. We were heading for "Cooper's Rock" in West Virginia, saw a sign for "Laurel Caverns" and headed there instead.Turned out to be pretty awesome. The biggest cave in Pa. I've been in caves before but never a mile in. They have more than 3 miles of cave open for exploration. One reason for this post is because of something I have a little trouble understanding. Supposedly in caves you don't have complete control of our senses. An incline may not seem as steep as it is or a hole may be deeper than it appears and so on. At one point we were climbing an incline upwards and came to a hand rail about 8 ft. in length. From the lower point, the handrail looked lower at the upper point and higher at the lowest point. Our guide placed a golf ball at the top (lowest point) and the balled appeared to roll upward to the bottom point. He told us that it was just an illusion and that the rail actually went downward but only appears to go upward. I still don't get it. Had a great day none the less. Anyone?