The Oregon Vortex is a roadside attraction located in Gold Hill, Oregon, in the United States. It consists of a number of interesting effects which skeptics believe to be optical illusions, but which the attraction's proprietors claim are the result of paranormal properties of the area (see gravity hill). It is located at .
According to the locals, a gold assay office built in the area in 1904 slid from its foundation in the early teens, coming to rest at an odd angle. Odd angles seem to create an illusion of objects seemingly rolling uphill. The same optical illusion can be seen in Pennsylvania's Laurel Caverns and at Santa Cruz, California's Mystery Spot which are copies of the The House of Mystery at The Oregon Vortex. Oregon Vortex is also famous for "height change" as the relative height of the two people changes varying on where they stand.[1] Most people believe this effect happens due to a distorted background which results in a forced perspective, as with an Ames room.[2] It should be noted, that photographs published at the official website of the attraction appear to demonstrate the same apparent height anomaly even when the potentially confusing perspectives of the background are removed. However, while the taller of the figures does indeed change dramatically in size depending on whether he stands on the side that 'makes you shorter' or the side that 'makes you taller', the shorter of the two figures remains the same size in all photos, no matter which end of the plank he stands on, thus indicating clearly that the photos are digitally altered. Photos taken by independent parties and posted online do not show a similar discrepancy in size once the illusion caused by the background is removed.