While some of it truly is still a Mystery and there are many theories the most widely accepted theory is related to the large iron deposits in the ground. You can stand just outside the affected area and a pendulum will take exactly the same amount of force to move in both directions but inside the affected area the same pendulum will take almost twice as much force to push one direction as the other. It is theorized that in addition to the earth's gravitational pull there is a large enough mass of iron deep in the ground that you are experiencing a gravitational pull towards it as well. When you visit the tour guides will cover the history and several of the theories and then walk you thru a series of demonstrations that you can then try on your own.
It's absolutely a place you should visit, but take some friends. I love this place and my husband and I are in opposition on it. I believe in the anomaly but he doesn't. It's so much fun. Enjoy!
The slope that you see is less than the opposite slope that it is built on. We have a similar place in florida where you can stop your car, put it in neutral and it will roll backward, up the hill.
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