"Regishi Island Strategies and Water Marks" (2-32-1, Shinkawa, Chuo-ku)
tide level was defined as the average tide level in Tokyo Bay (1884), and was used as a standard for zero altitudes. The altitude of the "Japan Standard", which was established in Nagata-cho, Chiyoda-ku in 1891, was determined by surveying from the intersection. At present, the standard tide center has been replaced by an oil pot tide center in Sagami Bay, but it is an important historical site in the history of modern surveying technology in Japan.
Tour of Japan Standard Field (Chiyoda-ku)
June 3 was one of the events related to the survey day (the survey method was promulgated on June 3, 1949), Japan's standard point and open to the public. I can't usually see the door closed, but I've seen it for the first time. It was a very interesting event lecture.
In the early Meiji era, a British-style benchmark was set up, and a method similar to an immortal character was carved into immortal objects, and heights were surveyed. In Western Europe, we heard that there were many cobblestones, and instead of digging holes on the road surface to set a benchmark, they carved symbols on the wall and set equipment on the horizontal line (nogroove). Since then, the surveying method has changed in Japan, and punctuality standards have been no longer used, and since then, it seems that the number of remaining non-textual notations has decreased due to disasters, war disasters, or burials. In Chuo-ku, the standard sign is clearly present at the bottom of the "Ichiishibashi Lost Shirase Stone Mark". (The role as a benchmark has been completed.)
In addition, the related "Japan History Origin" is located in Minato-ku. This is also an important starting point.
