Ino Tadataka Memorial Hall is a museum located in Katori City, Chiba Prefecture, dedicated to the life and achievements of Ino Tadataka, a pioneering Japanese surveyor and scholar of geography and astronomy who lived during the Edo period.
Ino is famous for spending many years surveying Japan in detail and producing remarkably accurate maps of the country. The museum introduces his life, surveying techniques, instruments, and maps, allowing visitors to learn how one of Japan’s most important early cartographic achievements was accomplished.
The Ino Tadataka Memorial Hall first opened in 1961. It was established to preserve and display valuable surveying instruments, maps, and other materials associated with Ino Tadataka. These materials were donated by his descendants and had been designated Important Cultural Properties in 1957.
When the museum first opened, a storage facility was built next to the former Ino residence to protect these important historical materials.
In 1998, a new museum building was constructed along the Ono River, directly across from the former Ino residence. The reinforced-concrete building has approximately 1,000 square meters of floor space.
Its exterior incorporates elements inspired by traditional Japanese townhouses and storehouses, allowing the building to blend naturally with the historic streetscape of Sawara. The Sawara district was designated an Important Preservation District for Groups of Traditional Buildings in 1996, and the museum’s design reflects the character of this historic town.
One of the first exhibits visitors encounter is a reproduction of the Portrait of Ino Tadataka. The original portrait was painted after Ino’s death by Aoki Katsujirō, an artist who had accompanied him during his surveying journeys and recorded landscapes along the way.
Although Ino originally came from a merchant background, the portrait depicts him as a man of samurai status, wearing the traditional pair of swords. A Chinese-style inscription praising Ino’s character was added above the portrait by Kuboki Chikusō, a Confucian scholar from the same region.
The exhibition “Japan as Seen through the Ino Maps and Landsat” provides a fascinating comparison between historical maps and modern satellite imagery.
Images of Ino’s maps are displayed alongside Landsat satellite photographs, allowing visitors to compare the Edo-period maps with modern views of Japan. This interactive comparison demonstrates how remarkably accurate Ino’s maps were considering the surveying technology available at the time.
Another section introduces Sawara as it was during the Edo period, when the town flourished through commerce and transportation along the Ono River.
Visitors can learn about the Ino family’s life and the development of the town. A model of a Takase boat, a type of riverboat used to transport goods, also illustrates how people and merchandise moved between Sawara and Edo, present-day Tokyo.
One of the most remarkable aspects of Ino Tadataka’s life is that his greatest achievements came during the second half of his life. After retiring from his successful career as a merchant at the age of 50, he began studying astronomy and calendar science.
He later traveled to Edo, where he became a student of Takahashi Yoshitoki, an astronomer who served the Tokugawa shogunate. Under Takahashi’s guidance, Ino developed his knowledge of astronomy and surveying.
At Takahashi’s recommendation, Ino conducted surveys of Ezo, present-day Hokkaido, and eastern Japan. The results impressed the shogunate, and he was eventually entrusted with the task of surveying the country on a national scale.
His nationwide surveying activities continued for approximately 17 years. The enormous amount of data he and his surveying team collected ultimately formed the basis for detailed maps covering Japan.
The museum also displays books that Ino copied by hand while studying under Takahashi Yoshitoki. These materials provide insight into how he learned astronomy, mathematics, and surveying techniques and how seriously he approached his studies later in life.
The museum’s most important attraction is its collection and presentation of Ino maps, known in Japanese as “Inōzu.” These maps represent one of the great achievements of Japanese cartography during the Edo period.
Visitors can see maps in several formats, including large-scale maps, medium-scale maps, small-scale maps, and special maps. Together, these exhibits show the enormous amount of work involved in surveying and mapping the Japanese archipelago.
The exhibits explain how Ino and his team traveled throughout Japan, conducted measurements, recorded geographical information, and organized the results into detailed maps.
Considering that the surveys were carried out more than 200 years ago, the accuracy of the resulting maps is particularly impressive. Comparing the historical maps with modern maps and satellite images allows visitors to appreciate the technical skill and dedication behind Ino’s work.
The museum also introduces maps created before Ino’s surveys. By comparing these earlier representations of Japan with the Ino maps, visitors can better understand how Japanese geographical knowledge developed over time.
The displays also show the location of Sawara and provide a broader look at how Japan was represented before accurate nationwide surveying became possible.
The museum presents videos and other materials about Ino’s extraordinary later life. Beginning his studies of astronomy and surveying after the age of 50, he went on to undertake extensive surveying journeys across Japan.
His story demonstrates that significant achievements can be made even after the traditional milestones of adulthood. His dedication, curiosity, and determination continue to inspire visitors today.
In 2010, the collection known as the “Materials Related to Ino Tadataka”, held by the Ino Tadataka Memorial Hall, was designated a National Treasure of Japan.
The collection contains a remarkable 2,345 items, including maps and drawings, documents and records, letters, books, and surveying instruments. Together, these materials provide an important historical record of Ino’s life, studies, surveying activities, and the intellectual culture of the Edo period.
Maps and drawings: 787 items
Documents and records: 569 items
Letters: 398 items
Books and manuscripts: 528 items
Surveying instruments and related equipment: 63 items
The museum is open from 9:00 a.m. to 4:30 p.m. It is generally closed on Mondays, although it may open when Monday is a public holiday. The museum is also closed during the New Year holiday period.
Admission is 500 yen for adults and 250 yen for elementary and junior high school students.
Discounted group admission is available for groups of 15 or more: 450 yen for adults and 200 yen for elementary and junior high school students.
The museum is approximately a 10-minute walk from Sawara Station on the JR East Narita Line.
By car, it takes approximately 15 minutes from the Sawara-Katori Interchange on the Higashi-Kanto Expressway.
The Ino Tadataka Memorial Hall offers a unique opportunity to discover the story behind some of Japan’s most important historical maps. Rather than simply displaying old maps, the museum explains how Ino Tadataka studied, traveled, measured, and recorded Japan during the Edo period.
For international visitors interested in Japanese history, geography, science, traditional cartography, or the Edo period, the museum provides an engaging way to understand both the remarkable achievements of one individual and the society in which he lived.