Editing Triangulation station (section)

===Japan===
In Japan, there are five classes of {{nihongo|triangulation stations|三角点|sankakuten|lit. 'three corner points'}}:

;{{nihongo|Class 1|一等三角点|ittō sankakuten}}
:They are installed approximately every {{convert|40|km|mi}}, with smaller ones (as necessary) about every {{convert|25|km|mi}}.<ref name="class1distance">{{cite web|url=http://www.gsi.go.jp/MUSEUM/TOKUBE/KIKA5-sanka1.htm|title=一等三角測量とは|language=ja|trans-title=About Class 1 Triangulation Stone Markers|access-date=20 April 2015|publisher=Geospatial Information Authority of Japan|archive-date=27 April 2015|archive-url=https://web.archive.org/web/20150427143508/http://www.gsi.go.jp/MUSEUM/TOKUBE/KIKA5-sanka1.htm|url-status=dead}}</ref> There are about 1000 throughout Japan. The pillars are {{convert|18|cm|in}} on a side, and each pillar is anchored with two very large perpendicular rocks buried underground.<ref name="class1construction">{{cite web|url=http://www.gsi.go.jp/MUSEUM/TOKUBE/KIKA5-sanka6.htm|title=一等三角点標石の構造|language=ja|trans-title=Class 1 Triangulation Stone Marker Construction|access-date=20 April 2015|publisher=Geospatial Information Authority of Japan|archive-date=27 April 2015|archive-url=https://web.archive.org/web/20150427143506/http://www.gsi.go.jp/MUSEUM/TOKUBE/KIKA5-sanka6.htm|url-status=dead}}</ref>

;{{nihongo|Class 2|二等三角点|nitō sankakuten}}
:They are installed approximately every {{convert|8|km|mi}}. There are about 5000 throughout Japan, and the pillars are {{convert|15|cm|in}} on a side. Each pillar is anchored with a very large perpendicular rock buried underground.

;{{nihongo|Class 3|三等三角点|santō sankakuten}}
:There are about 32,000 installed throughout Japan, with one approximately every {{convert|4|km|mi}}. The pillars are {{convert|15|cm|in}} on a side, and each pillar is anchored with a large perpendicular rock buried underground.

;{{nihongo|Class 4|四等三角点|yontō sankakuten}}
:They are installed approximately every {{convert|2|km|mi}}, and there are about 69,000 throughout Japan. The pillars are {{convert|12|cm|in}} on a side, and each pillar is anchored with a large perpendicular rock buried underground.

;{{nihongo|Class 5|五等三角点|gotō sankakuten}}
:These markers were installed in 1899 and are the predecessors to the modern triangulation stations used in Japan today. They are generally not used anymore since the installation of the Class 1-4 stations. Some of them still exist at various locations throughout Japan.

<gallery>
3rd class triangulation point in Shiroyama Park in Inagi.jpg|Class 3 triangulation point in Shiroyama Park in [[Inagi, Tokyo]]
</gallery>