Tadataka Ino

Japanese surveyor who created first precision map of Japan through 17-year walking survey

Beginning at age 55 in 1800, Tadataka Inō (1745-1818) conducted history's most remarkable pedestrian cartography project. His team walked 43,000 km across Japan, using celestial navigation and chain measurements to create 1:36,000 scale maps with 0.1° longitude accuracy.

Modern GIS analysis reveals Inō's maps align with satellite imagery within 0.01° margin - astonishing precision for Edo-period technology. His survey methods pioneered error correction through repeated lunar observations, predating modern statistical redundancy techniques.

The Inō-zu maps remained classified until 1923 due to military sensitivity. When opened, they revealed forgotten trade routes now revitalized as cultural heritage trails.