During a research stay with the University of the Philippines, Los Baños, I got a chance to visit a so-called magnetic mountain. Magnetic mountains are geological structures with some slope (strictly speaking, a slope-or a height-not necessarily counting for a mountain but for a hill) that allow every rolling or flowing object or substance to appear to roll or flow uphill.

In 1997, I carried out preliminary experiments concerning magnetic fields, hidden iron, etc. on a magnetic mountain near Los Baños leading to the (obvious) result that most likely an optical illusion caused the allegedly magnetic effect (figure 1). However, it was startling to observe that even on photographs the optical illusion remains relatively intact (see figures 2 and 3). As one can see, an upward slope that goes actually downwards, and a downward slope that goes actually upwards seem to be clearly visible on the pictures. Obviously, the lack of right-angled structures plus the bend of the street itself make it impossible to identify the optical illusion.

Even water seems to flow upwards.

A car (parking gear) slowly rolling “upwards.”

A theory brought forward by a student was that a strong magnetic field might be the force that pushes the materials (usually cars of local tourists) uphill. Such a strong magnetic field seems unlikely, and amongst the materials tested by us on the Los Baños hill were glass marbles of around 1 cm diameter, empty plastic bottles, and water that was poured out, all of them known to be not magnetic under normal conditions. All materials, however, did roll or flow in a seemingly upward direction. From scientists in Canada, Thailand, and elsewhere I learned that “magnetic mountains” exist in several countries, and that accounts of them might exist in popular science literature. Since none of the tourist departments that I contacted until now cooperated in this matter, I would like to ask the readers of the Skeptical Inquirer to report cases of magnetic mountains that they have either observed themselves, or of which they got to know by any other means. Every piece of information, no matter how small, will be appreciated. I would also like to encourage national and local skeptical organizations to spread the request amongst their communities.

We are currently planning a proper geological survey of as many magnetic mountains as possible. If there is anything you can contribute, please let me know at forensic@benecke.com, or at the following postal address: Mark Benecke, Int. Forensic Res. & Consulting 250411 Pastfach, 50520 Cologne, Germany.

Editor’s Note: We're glad to publish the query, but we'd be willing to bet that this “magnetic mountain” is indeed an optical illusion. For Skeptical Inquirer articles on related matters see the short section “Magnetic Hill” in “Canada’s Mysterious Maritimes,” by Joe Nickell, January/February 2000 (also the letter and reply in May/June 2000 issue, p. 68); “Believing What We See, Hear, and Touch: Delights and Dangers of Sensory Illusions,” by Rainer Wolf, May/June 1996; “It’s All an Illusion! And Here’s How It’s Done,” by Ray Hyman, and “Explanation of the Impossible Box and the Plank Illusion,” by Jerry Andrus, both Spring 1994; and “Spook Hill: Angular Illusion,” by Guss Wilder, Fall 1991. Further research on allegedly magnetic mountains including experimental data is performed by Mark Benecke is in press with the German Skeptiker.