Slope illusion 2

Outdoor tilt illusion where an ascending slope appears to descend or a descending slope appear to ascend

e.g. Magnetic Hill in Canada; Wikipedia

since October 20, 2011 Slope illusion 3


A survey of the "mysterious slope" located in Towa-town, Hanamaki-city, Iwate-prefecture, Japan

October 14, 2011, reported by Akiyoshi Kitaoka and Seiichi Tsuinashi, supported by a JSPS kaken-hi grant and R-GIRO

Copyright Akiyoshi Kitaoka 2011 (October 17)@photo taken on October 14, 2011

This slope appears to ascend, but it is actually a descent.


"Towa-town sightseeing spot Mysterious Slope: An ascending slope where a car descends? How to experience: (1) Set the gear in neutral. (2) Loose the brake. Aha!"


This bus is actually descending the slope, but it appears to ascend.


This bus is actually descending the slope, but it appears to ascend.


Physically the left slope is a steep descent and the right one is a gentle descent, but the latter appears to be an ascent.

cf. Bressan, P., Garlaschelli, L. and Barracano, M. (2003) Antigravity hills are visual illusions. Psychological Science, 14, 441-449.


This slope appears to be a descent, but it is actually an ascent.


This person, Dr. Tsuinashi, is ascending the slope.


A view from a lower place before the crossing with which the mysterious slope connect


The mysterious slope, the left one, appears to be an ascent even when observed in a mirror, though it is actually a descent.


The mysterious slope, the right one, appears to be an ascent, though it is actually a descent.


The mysterious slope, the right one, appears to be an ascent, though it is actually a descent. Dr. Tsuinashi is taking pictures.


The mysterious slope observed in this mirror appears to be as steep as or steeper than the left ascent.


Here it is!


This board informs that the mysterious slope is 4.2km distant from this main street. This information is correct.


This board informs that the mysterious slope is 3.2km distant from this main street. Was there another mysterious slope?



A survey of another "mysterious slope" located in Towa-town, Hanamaki-city, Iwate-prefecture, Japan

October 14, 2011, reported by Akiyoshi Kitaoka and Seiichi Tsuinashi, supported by a JSPS kaken-hi grant and R-GIRO

This slope appears to be an ascent, though it is actually a descent.


This slope appears to be an ascent, though it is actually a descent.


The slope in front appears to be an ascent and the connecting slope appears to be a descent, though both are descents.


This slope may appear to be a descent, though it is actually an ascent.


The slope in front appears to be a descent and the connecting slope appears to be an ascent, though both are ascents.

Photo taken by Seiichi Tsuinashi Copyright Seiichi Tsuinashi 2011 (October 18)


Here it (Towa-town) is!


Seiichi's slope illusion pages


Slope illusion 1

Slope illusion 3 (Moving-back slope in Hashikami, Aomori, Japan)


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