The Only Place in Japan with 10-Degree Intersection of Latitude and Longitude

40°N and 140°E Crossing Point

(Ogata Village, Akita Prefecture)

【Kiri-ga-ii (切がいい)】 means "a nice round number" in English. People prefer nice round numbers (kiri-ga-ii) over odd numbers. When something is a nice round number (kiri-ga-ii), somehow people often want to commemorate it. For example, the 10th anniversary, the 100th day of school, 2,000 hits in Major League Baseball, and so on. Latitude and longitude are no exception.

Ogata Village in Akita Prefecture is the only place in Japan with a 10-degree intersection of latitude and longitude: 40 degrees north latitude and 140 degrees east longitude. The area is reclaimed land that was once the second-largest lake in Japan, Lake Hachirō, which has been filled since 1957. If the land had not been filled, the 10-degree confluence would be underwater, and there would be no 10-degree intersection on land in Japan.

A fine monument consisting of four poles stands to mark the latitude-longitude confluence. It is located on an unpaved access road leading to rice fields along an irrigation canal. There is nothing else but vast, orderly farmland spreading as far as the eye can see. However, people visit this place to see the monument because of its nice round number (kiri-ga-ii)

There are 39 integer degree confluences on land in Japan. For example, one degree to south (N39, E140) is located on Sakata City, Yamagata Prefecture but nobody care that point because it is not a nice round number (kiri-ga-ii).

The location of the monument is not exactly on the longitude of 140 degrees east. The actual location is about 450 meters to the southeast. The latitude was originally defined with reference to “the Japanese origin of longitude and latitude”, which is located in Minato Ward, Tokyo, near the Tokyo Tower. This reference point was measured and defined using astronomical observations in 1918. In 2002, the definition of the longitude and latitude was changed to align with the global standard using a satellite navigation system. As a result, the reference latitude was also changed.

There are other places with monuments marking 40 degrees north latitude in Iwate Prefecture, and 140 degrees east longitude in Tochigi and Chiba Prefectures. Another notable line of longitude is 135 degrees east, which is the reference line for Japan Standard Time. Nishiwaki City in Hyogo Prefecture, which claims to be the navel and center of Japan, is another destination at the confluence of 35 degrees north latitude and 135 degrees east longitude.