Slope illusion 8

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 February 18, 2013


A survey of the illusory slope located in Nakatane-town, Tanegashima-island, Kagoshima-prefecture, Japan

February 2, 2013, reported by Akiyoshi Kitaoka and Seiichi Tsuinashi, supported by a JSPS kaken-hi grant and R-GIRO

The illusory slope in Nakatane-twon, Tanegashima-island

Copyright Akiyoshi Kitaoka 2013 (February 17) photo Fenruary 2, 2013

This slope is a loose descent (0.9 deg) toward the sea, but it appears to be an ascent.


The nearer slope appears to be an ascent but is a loose descent. This is evident considering the position of the horizon, as shown below.


This slope is a loose descent (0.9 deg) toward the sea, but it appears to be an ascent.


This road physically tilts down in the left direction, but it does not appear so.


This slope is a loose descent (0.9 deg) toward the sea, but it appears to be an ascent.


Isn't this slope an ascent toward the sea? No, it isn't, as shown below.



The nearer slope appears to be a descent but it is a loose ascent (0.9 deg). The farther slope is a steep ascent (5.7 deg).


The nearer slope appears to be a descent but it is a loose ascent (0.9 deg). The farther slope is a steep ascent (5.7 deg).


The farther slope appears to be an ascent toward the sea but it is a loose descent (0.9 deg). The nearer slope is a steep descent (5.7 deg).



(photo by Dr. Tsuinashi)

The farther slope appears to be an ascent toward the sea but it is a loose descent (0.9 deg). The nearer slope is a steep descent (5.7 deg).




Slanting field

Probably the field is flat, but the farther side appears to be higher than the nearer one. Actually, the road is a steep descent.


Our new machine to measure the slant of a road


Dr. Seiichi Tsuinashi was measuring the distance.


"Rock of a man (upper) and a chimpanzee (lower) viewed from the Tanegashima Space Center"

photo by Seiichi Tsuinashi 2013 (February 3)



Tanegashima Space Center
photo by Seiichi Tsuinashi 2013 (February 3)


Seiichi's slope illusion pages


Slope illusion 7 (Danjo-zaka and Okyo-zaka in Amakusa-Shimojima, Kumamoto, Japan)

Slope illusion 6 (Slope-ascending river in Miyama, Nantan, Kyoto, Japan)

Slope illusion 5 (Ghost slope in Okagaki, Onga-county, Fukuoka, Japan)

Slope illusion 4 (Slope-ascending water in Tanushimaru, Kurume, Fukuoka, Japan)

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

Slope illusion 2 (Mysterious slope in Towa, Iwate, Japan)

Slope illusion 1 (Mystery zone in Yashima, Takamatsu, Kagawa, Japan, etc.)


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