everyone in california has a bumper sticker from here.
“The Mystery Spot is a gravitational anomaly located in the redwood forests just outside of Santa Cruz, California. It is a circular area of effect around 150 feet or 46 meters in diameter. The Mystery Spot was discovered in 1939 by a group of surveyors and opened to the public in 1940. The Mystery Spot has amazed and perplexed hundreds of thousands of visitors from all over the world, and many return time and time again to experience these puzzling variations of gravity, perspective, and height. Some speculate that cones of metal were secretly brought here and buried in our earth as guidance systems for their spacecraft. Some think that it is in fact the spacecraft itself buried deep within the ground. Other theories include carbon dioxide permeating from the earth, a hole in the ozone layer, a magma vortex, the highest dielectric biocosmic radiation known anywhere in the world, and radiesthesia. Whatever the cause is, it remains a mystery.”
-From the description on mysteryspot.com