is a 43 km long Japanese aqueduct that was constructed by the Tokugawa shogunate

Tokugawa shogunate

The Tokugawa shogunate, also known as the and the , was a feudal regime of Japan established by Tokugawa Ieyasu and ruled by the shoguns of the Tokugawa family. This period is known as the Edo period and gets its name from the capital city, Edo, which is now called Tokyo, after the name was...

 to supply drinking and firefighting water from the Tama river

Tama River

The is a major river in Yamanashi, Kanagawa and Tokyo Prefectures on Honshū, Japan. It is officially classified as a Class 1 river by the Japanese government....

 to Edo

Edo

, also romanized as Yedo or Yeddo, is the former name of the Japanese capital Tokyo, and was the seat of power for the Tokugawa shogunate which ruled Japan from 1603 to 1868...

, providing irrigation water around farm villages.

Construction of the aqueduct, which began in 1653, was preceded by the Bekko Shoemon arson

Arson

Arson is the crime of intentionally or maliciously setting fire to structures or wildland areas. It may be distinguished from other causes such as spontaneous combustion and natural wildfires...

 conspiracy. Bekko led a group of rōnin

Ronin

A or rounin was a Bushi with no lord or master during the feudal period of Japan. A samurai became masterless from the death or fall of his master, or after the loss of his master's favor or privilege....

 who planned to depose and kill Ii Naotaka

Ii Naotaka

was a Japanese daimyo of the early Edo period who served under the Tokugawa shogunate. He was the son of the famous Tokugawa general Ii Naomasa.Naotaka served in the Siege of Osaka in his brother Naokatsu's stead, where he would gain tremendous favor for his exploits at Tennoji. After the battle,...

 and his party. They intended to burn down temples of Edo on August 20, 1652, a religious holiday, and kill their targets during the confusion. Bekko was arrested on the eve of the planned strike, tortured and crucified. The problem of containing fires remained: the city was served by a single, and insufficient, Kanda Aqueduct.

The people of Kojimachi

Kojimachi

is a neighborhood in Chiyoda, Tokyo.Prior to the arrival of Tokugawa Ieyasu, it was known as . The area developed as townspeople settled along the Kōshū Kaidō. In 1878 Kōjimachi became a ward in the city of Tokyo. It was the forerunner of Chiyoda which is now a special ward.The Kōjimachi ward was...

 and Shibaguchi requested permission to build another aqueduct, drawing the waters of the Tama river. The government provided 7,500 ryo

Ryo

Ryo may refer to:* The Japanese kana digraph ryo, ryō, or ryoh * Ryō , a gold piece in pre-Meiji era Japan worth about sixty monme or four kan...

 for the construction, 3,000 ryo were collected by public subscription. The whole aqueduct was constructed in 18 months. The two "engineers" in charge of construction were "mere peasants". After the completion they were rewarded with family name Tamagawa and appointment as managers of the aqueduct. However, the new aqueduct did not save Edo from the devastating Great Fire of Meireki

Great Fire of Meireki

The , also known as the Furisode Fire, destroyed 60-70% of the Japanese capital city of Edo on March 2, 1657, this is the third year of the Meireki Imperial era...

(1657).