Yamanote Line Marks 100th Year of Operation as Loop Train in Nov., Grows as Tokyo’s Lifeline with Eye on Future

The Yomiuri Shimbun

13:36 JST, November 17, 2025

The Yamanote Line in November marked 100 years of operations as a loop line.

Regarded as the “aorta of the Tokyo metropolitan area,” the line connects major terminal stations including Tokyo, Shinjuku and Ueno, carrying around 1 million passengers each day.

The line, which consists of 30 stations in a 34.5-kilometer loop, serves as the lifeline of central Tokyo, and its history mirrors the capital’s development.

The origins of the Yamanote Line date to the Meiji era (1868-1912). In 1885, its predecessor, Nippon Railway’s Shinagawa Line, opened between Shinagawa and Akabane stations, with Shibuya and Shinjuku stations also commencing operations.

Its main purpose was facilitating the transport of raw silk and coal for export from Gunma and Ibaraki prefectures to the Port of Yokohama. As much of the route traversed higher ground in the area, the name “Yamanote Line,” meaning “hillside line,” was adopted in 1901.

Full-fledged passenger service expanded during the Taisho era (1912-26) and early in the Showa era (1926-89).

As areas such as present-day Chiyoda and Bunkyo wards became overpopulated, residential areas spread into the suburbs, making the line a vital commuting route for workers and students.

With the development of private railways proceeding in tandem, connecting the Yamanote Line to their terminal stations led the line to grow into a core commuter train route in central Tokyo.

Elevated track, circular operation

Although the opening of Tokyo and Kanda stations made the operational section almost circular, there was no connection between Ueno and Kanda stations — located in densely populated areas. To address this, the government proceeded with the construction of elevated tracks.

The section between Shimbashi and Tokyo stations was built with bricks, while the section between Tokyo and Ueno stations was constructed with reinforced concrete.

“Considering factors such as earthquake resistance, they employed the latest technology at the time,” said railway historian Kenji Nakamura, 79.

The construction of the elevated track section, which began in 1923, was completed in 1925 — just six months behind schedule — despite huge damage wrought on stations during the Great Kanto Earthquake in 1923. On Nov. 1, operation of the line in a full circle finally started.

“With circular operation, efficient transportation was made possible,” said Shigeru Onoda, an adviser at the Railway Technical Research Institute, a public interest incorporated foundation. “Countries with circular lines running in their capitals, besides the subway system, are rare.”

During Japan’s rapid economic growth period in the postwar years, the Yamanote Line evolved along with the country’s development. In 1963, the eight-car 103 series debuted, establishing the line’s signature light-green color. In 1968, operation of 10-car trains commenced.

Redevelopment for the next century

A new station, Takanawa Gateway, opened in 2020 between Tamachi and Shinagawa stations, marking the first new station on the line in 49 years.

East Japan Railway Co. (JR East), Tokyu Corp., and Tokyo Metro Co. are currently moving ahead with what is called a “once-in-a-century large-scale redevelopment” project around Shibuya Station, an undertaking that is expected to be completed in fiscal 2034.

“We will build stations and towns that will continue to be loved for the next 100 years,” said a JR East official.

In addition, new technologies are being introduced for train operations. As early as fiscal 2028, trains capable of autonomous operation will be adopted. By 2035, the implementation of fully autonomous operation, where the conductor does not need to be qualified as a train driver, is planned.

For rolling stock and track maintenance, robotics and AI will be utilized, allowing employees to focus on human-centered services and emergency response, thereby improving overall efficiency, according to JR East.