Mountain elevation, triangulation points and elevation points

Mountain heights shown on maps and in books are based on surveys by the Geospatial Information Authority of Japan (GSI). The GSI publishes the names, highest points and elevations of 1,003 major mountains in Japan, and updates them for crustal movement and other changes.

The reference level

As set out in the Survey Act, elevations are measured from the mean sea level of Tokyo Bay. On remote islands, the mean sea level around the island may be used instead.

Triangulation, elevation and surveyed points

The GSI list notes how each elevation was determined:

• Triangulation point: the elevation of the triangulation point (a survey benchmark) on the summit, rounded to the nearest metre.
• Elevation point: measured by aerial photogrammetry.
• Surveyed point: measured on site.

Because the list gives the elevation of each mountain's highest point, mountains marked with an elevation or surveyed point have their highest point measured by photogrammetry or on-site survey.

Elevations in this catalog

Of the 156 mountains, 127 use the GSI list of major mountains (March 31, 2026 edition). The other 28 use the triangulation or elevation points shown on GSI Maps; triangulation point values are given to one decimal place.

Mount Kirigishi (Ashibetsu City) has no elevation figure at its summit on GSI Maps, so we show the highest value near the summit in the GSI elevation tiles (10 m mesh), marked "about".

By type: 101 triangulation points, 53 elevation points, 1 surveyed points and 1 from elevation tiles.