01 / Longitude and latitude origin
Japan's reference point for longitudeand latitude sits in Azabudai 2-chome.

A Survey Act enforcement order fixes the Japanese Geodetic Datum Origin at the cross-point of the metal marker in Azabudai 2-chome, Minato Ward. In 1892 the center of the Tokyo Astronomical Observatory's meridian circle was set as the origin.
- Set as the origin in 1892 (Meiji 25)
- Center of the observatory's meridian circle
- Ward-designated historic site

