History Of The Japan Railway Company

Chronology of the establishment of JR (Japan Railway Company) from JNR (Japan National Railways)

AD Japanese calendar record
1871. 4th year of Meiji era (1868.9.8-1912.7.13) Tunnel between Osaka and Kobe completed.
1872. 5th year of Meiji era (1872) The 150 class steam locomotive [Japan’s first steam locomotive imported from the U.K.] is put into full service between Shimbashi, Shinagawa and Yokohama.
1889. The 22nd year of Meiji The entire Tokaido Line between Shimbashi and Kobe was opened to traffic. The journey takes about 20 hours.
1891. 1891 The entire Tohoku Main Line between Ueno and Aomori was opened to traffic. The time required is about 26 hours.
1895. 28th year of Meiji era Kyoto Electric Railway, the first electric railway, begins operations.
1913. 1913 The construction of double-tracking of all lines of the Tokaido Main Line is completed.
1918. Taisho 7 Employment of female conductors (Mino Electric Railway)
1925. Taisho 14 Started circular operation of the Yamanote Line.
1926. Taisho 15 German-made ticket vending machines are installed at Tokyo and Ueno Stations.
1927. 1990 The first subway line between Ueno and Asakusa opens. Tokyo Subway System 1000 Series
1930. 1930 Super-express train “Tsubame” begins service between Tokyo and Kobe on the Tokaido Main Line.
1934. 1934 The Tanna Tunnel on the Tokaido Main Line is completed.
1936. 1936 D51 class steam locomotive is inaugurated.
1937 (Sino-Japanese War) – 1939 (World War II) – 1945 (end of war)
1942. 1942 The undersea tunnel between Shimonoseki and Moji is completed during the war.
1960. 1960 The diesel limited express service will begin operation between Ueno and Aomori on the Tohoku Main Line.
1963. 1963 Start using Automatic Train Stop System (ATS) in some sections.
1964 1964 Tokaido Shinkansen starts service. 0 series Shinkansen
1966. 1966 Completes installation of Automatic Train Stop System (ATS) equipment on all Japan National Railways lines.
1972. 1972 The Sanyo Shinkansen Line between Shin-Osaka and Okayama begins service.
1975. 1975 The Sanyo Shinkansen Line between Okayama and Hakata begins service.
1980. 1980 Begins using Automatic Train Control (ATC) on the Yamanote and Keihin-Tohoku Lines.
1982 1982 The Joetsu Shinkansen Line between Omiya and Niigata is opened.
1985. 1985 Started to use the Tohoku Shinkansen and Joetsu Shinkansen to “Ueno Station”.
1987 1987 March 31 will be the last day of Japan National Railways.
1987 1987 It will start as seven new companies as JR.
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Jurisdiction of East Japan Railway Company

JR East is a passenger railway company that took over the railway business from Japan National Railways (JNR) on April 1, 1987.
JR East has the longest operating routes of all the companies in the JR Group, with a total of 7,526.8 km of operating kilometers.
The lines under its jurisdiction are: Yamanote Line, Keihin Tohoku Line, Yokohama Line, Negishi Line, Nambu Line, Musashino Line, Akabane Line, Saikyo Line, Kawagoe Line, Chuo Main Line (Chuo Line Rapid, Chuo and Sobu Lines), Ome Line, Itsukaichi Line, Sobu Main Line (Sobu Rapid, Chuo and Sobu Lines), Keiyo Line, Tokaido Main Line, Yokosuka Line (Shonan Shinjuku Line), Tsurumi Line, Sagami Line, Hachiko Line, Takasaki Line, Takasaki Line, Hachiko Line, Takasaki Line, and Sagami Line. The lines are vast: Hachiko Line, Takasaki Line, Joetsu Line, Azuma Line, Ryomo Line, Nikko Line, Karasuyama Line, Tohoku Main Line (Utsunomiya Line), Mito Line, Joban Line (Joban Kaisoku Line, Joban Loose Line), Suigun Line, Uchibo Line, Sotobo Line, Narita Line, Kashima Line, Kururi Line, Togane Line, and so on.
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History of Japan National Railways (JNR) to JR (Japan Railway Company)

After World War II, the national railway business suffered from the inflation caused by the defeat in the war, as well as the employment of demobilized soldiers and repatriates from overseas.
In this chaotic period, the Japanese government established the Japan National Railways (JNR) in June 1949 as a government-funded special corporation to take over the national railway business. After its establishment, JNR promptly started to lay off its 95,000 employees.
As a result, the “Mitaka Incident” and the “Shimoyama Incident” are said to have left behind major problems on the side of labor politics. In addition, serious accidents such as the “Sakuragicho Incident,” which was caused by poorly designed wartime vehicles and ground facilities, left further problems in their wake. On the other hand, the total transportation capacity recovered to the prewar level by renewing old facilities and increasing the transportation capacity.
In 1958, the first limited express train, the Kodama (151 Series), was put into service, and in 1964, the Tokaido Shinkansen began service. Competition with automobiles and airplanes began to intensify during this period.
In 1960, the Advisory Committee of the Japanese National Railways submitted its “Opinion on Methods of Improving the Management of Japan National Railways”. The content of the report warned that “the excessive burden of building new local lines under national policy and the increase in labor costs due to excessive employment immediately after the war had ended were having a serious impact on the management of Japan National Railways”. As a result, Japan National Railways posted a deficit of 830 billion yen in fiscal 1964 (a single fiscal year).
The deficit continued to accumulate, but in November 1986, the National Diet passed a bill for the division and privatization of Japan National Railways. The liabilities to be dealt with in the privatization include the long-term debt of Japan National Railways, the debt of the Construction Corporation of Japan, the debt of the Honshu-Shikoku Bridge Authority (the share of JNR), and the resources of the Management Stabilization Fund (JR Hokkaido, JR Shikoku, JR Kyushu), which will be assumed by the Japan National Railways Liquidation Corporation, the Shinkansen Railway Holding Organization, and six new companies (JR East, JR Central Japan, JR West, JR Freight, Railway Communication, and Railway Information Systems). The total amount of the debt is 37.11 trillion yen. The total debt amounted to 37.11 trillion yen.
When the bubble economy showed signs of slowing down, it was found that interest payments of about 1 trillion yen would be incurred annually on this massive debt, and the redemption scheme quickly collapsed.
While it became impossible to redeem the debt, 24.2 trillion yen of government-guaranteed debt was transferred to the national general account.
The debt service is scheduled to be completed in 2057. This is a historical fact that we should never forget when we talk about JR.

In-house power generation facilities

052s-8 JR East is overwhelmingly different from other railway operators not only in terms of its routes.
We have our own power generation facilities. The Kawasaki Thermal Power Plant and Shinanogawa Power Plant are located in the area, and train operations are not affected in the event of a power outage from the Tokyo Electric Power Company (TEPCO).
The Kawasaki Thermal Power Station has a maximum capacity of 655,000 kW, and the Shinanogawa Hydroelectric Power Station has a maximum capacity of 449,000 kW, enough power to supply about 60% of the electricity used by JR East. The Kawasaki Thermal Power Station is scheduled to increase its power output by 75,000 kW from fiscal 2013 by starting work on the renewal of Unit 4.
Kawasaki Thermal Power Station (Google Earth )

Tokyo Area Transportation Management System (ATOS)

040s-4 The Tokyo Area Transport Operation Control System is a computer system for managing train operations and route control that was jointly developed by East Japan Railway Company and Hitachi, Ltd. and introduced in 1996.
It is commonly known as ATOS (Autonomous decentralized Transport Operation control System), and is an autonomous decentralized transport management system that uses a high-speed optical fiber network to connect the Tokyo Control Center (call sign: East Railways Control Center) with the trains, crew bases, and stations along the rail line. It is an autonomous decentralized transportation management system. The system centrally manages operation schedules, station route control, passenger information, maintenance work management, etc. When a train is delayed, the system controls the route of points, signals, etc. based on the revised operation schedule.
Shinagawa Station Passenger Information System
039s-5 At the same time, time adjustments and changes in the order of arrival and departure are immediately sent to each station and reflected in the passenger information system (see photo above left). Information on other lines in the Tokyo metropolitan area that may cause transport disruptions is also shared and displayed.
Departure time indicators (
 left photo) are used by ATOS to instruct the trains in service to adjust the interval between trains and when to suspend operation. It is located in the driver’s visual position at the stop station and displays “Hold, Notification, Extension, Departure”, etc. The “Notification” in the photo shows the train in front of the station.
The “Notification” shown in the photo indicates that the train will depart from this station after confirming that the preceding train has departed from the next station. When the train in front of the station is confirmed to have departed from the next station, the blinking light will go off earlier and the light will go off.
ATOS Departure Time Indicator
ATOS implementation route
District line interval
Central Area Command Chuo Rapid Transit Authority subway Tokyo – Takao
Chuo Main Line (central railway line in Tokyo) Takao – Kofu
Chuo Sobu Line Mitaka – Chiba
E-direction command Yamanote Line the whole line
Shonan Shinjuku Line Meguro River Signal Station – Ikebukuro
Jekubo Signal Station – Osaki
Keihin-Tohoku Negishi Line Omiya – Yokohama – Ofuna
Saikyo, Kawagoe and Hachiko lines Osaki – Omiya – Kawagoe
Kawagoe – Musashi Takahagi
Tokaido Direction Tokaido Main Line Tokyo – Yugawara
Yokosuka and Sobu Rapid Line Kurihama – Tokyo – Chiba
Nambu Line and Nambu Branch Line Kawasaki – Tachikawa
Shirate – Shin-Tsurumi Signal Station
Tokaido Freight Line Shin-Tsurumi Signal Station – Odawara
Northeast Command Utsunomiya Line (Chiba-Tokyo Railway) Ueno – Furukawa – Nasushiobara
Takasaki Line Omiya – Jinbohara
Shonan Shinjuku Line Ikebukuro – Omiya
Joban Direction Joban Line Rapid, Joban Line Ueno – Hatori
Joban Joko Line (Chiba-Tokyo Railway) Ayase – Toride

 

Major railway accidents (1950-2010)

Date of accident accident name Details of the accident
February 09, 1950 Shonan train fire accident A test train of Series 80 train (14 cars) was running between Hodogaya and Totsuka stations on the Tokaido Main Line when an electric arc was emitted from the pantograph of the 13th car, Moha 80027. The car and MOHA 80027 next to it caught fire and was destroyed. The cause was presumed to be that the pantograph was grounded by the foreign substance of the conductor which flew by the wind and got on the pantograph. In addition, the substation near the site did not detect the accidental current and kept the power on for about 25 minutes after the fire broke out, so firefighters were unable to extinguish the fire by spraying water from a fire truck, which was a factor that increased the damage. Therefore, after the accident, tests were conducted on the 1500V overhead lines that were still energized, and it was determined that water could be discharged by grounding the pipe mouth in consideration of the quality of the water.
April 24, 1951 Sakuragicho accident
(Five major postwar accidents of Japan National Railways)
A Keihin Line train (Type MOHA63, five-car train 1271B) was accidentally cut off during insulator replacement work at Sakuragicho Station and came into contact with an overhead wire that was hanging down, catching fire due to an electric current ground fault. The first car burned to the ground and the second car half burned, resulting in 106 fatalities and 92 seriously injured. At the time, the Series 63 trains used on the Keihin Line were of wartime design, and their shoddy construction was blamed for many deaths and injuries, leading to the strengthening of safety measures for the National Railways.
June 18, 1952 Passengers fell down in Nippori station The panelling of the south span bridge at the Nippori station of the Japan National Railways was damaged when it could no longer bear the weight of passengers, and dozens of people fell 7m to the tracks below. Eight people were killed and five others seriously injured when they were hit by a passing Keihin Tohoku Line Urawa-bound train. The cause of the accident was that the bridge over the tracks (built in 1928) had deteriorated, a fire broke out at a signal station in Ueno Station before dawn on the day of the accident, and the up train on the Tohoku Main Line had to stop temporarily at Nippori. It is said that the train was crowded with more than twice as many passengers as usual.
May 03, 1962 Mikawashima Accident
(Five major postwar accidents of Japan National Railways)
A down freight train (steam locomotive in tow) from Tabata Yard to Mito tried to enter the down main line from the freight line at Mikawashima Station on the Joban Line, but ran a stop signal, entered the safety lane, and derailed. Immediately after the lead locomotive interrupted the down line, the train departed Mikawashima Station one minute behind schedule and collided with a down train bound for Toride from Ueno, which was proceeding on the down line, interrupting the up line. About 6 minutes later, an up train bound for Toride came into the scene at high speed, crushing the lead cars of both trains, and causing many evacuees to be killed. Insufficient security measures for trains, equipment and the immediate aftermath were blamed for the accident, which subsequently led to the installation of Automatic Train Stop Systems (ATS) and train radio systems.
August 07, 1962 Nambu Line level crossing accident A down train collided with a truck that ignored the alarm and entered at the Class 3 level crossing between Tsudayama and Kuchi stations on the Nambu Line. Three people were killed when an up train collided with a down train that had obstructed the up train. This accident brought to light the problem of frequent level crossing accidents and led to the study of fundamental maintenance measures for level crossings, such as improving crossing facilities and making them multi-level, and the installation of level crossing obstruction warning devices was promoted as an immediate measure.
November 09, 1963 Tsurumi accident
(Five major postwar accidents of Japan National Railways)
Between Tsurumi and Shinkoyasu stations on the Tokaido Main Line, a down freight train running on the freight line (currently the Yokosuka Line) derailed, causing a triple collision with an up and down passenger train. In total, 161 people were killed and 120 were seriously injured. After an investigation, it was determined that the cause of the collision was a competitive derailment.
January 04, 1964 Tachikawa station tank car collision An express train stopped at Tachikawa station was hit by a tank car filled with gasoline and caught fire, seriously injuring two passengers. The fire spread quickly and destroyed a building of 1,600 square meters around it.
August 08, 1967 U.S. military fuel train collides and catches fire A freight train (electric locomotive EF10 and 20 hopper cars) bound for Hama-Kawasaki on the Chuo Line upstream crossed a stop signal and collided with the side of a freight train (electric locomotive EF10 and 18 tank cars) bound for Tachikawa on the Chuo Line passing through the crossing line at the Shinjuku Station on the Chuo Line. Aviation fuel leaking from the derailed and overturned tank car ignited, and the locomotive and three tank cars caught fire. Although no one was killed or injured in the accident, the firefighting work was delayed due to the time required to extinguish the intense fire and to remove the fuel from the tank cars that escaped the fire, as well as the restoration work.
July 16, 1968 Ochanomizu Station train rear-end collision A 2239F train (10 cars) bound for Toyota station was rear-ended by a 2201F train bound for Takao station on the Chuo Line. Both trains derailed 5 cars each, and 210 people were injured. The cause of the accident was attributed to human error by the driver of the following train, who exceeded the speed limit and was late in applying the brakes.
March 28, 1972 Rear-end collision in Funabashi station At Funabashi Station on the Sobu Main Line, at around 7:21 a.m., the up train 613C (Nakano-bound, 101 Series, 10-car formation) on the slow line was stopped due to signal trouble at the station when the following up train 711C (Mitaka-bound, 101 Series, 10-car formation) on the slow line rear-ended it, derailing the sixth car of the Mitaka-bound train. Fortunately, no one was killed, but because there were so many passengers on the train during the morning commuting hours, it was the worst accident in Japan in terms of the number of injured, with 758 people seriously or slightly injured. Just before the accident, a power line at the Warabi substation was disconnected, causing a power failure in the signaling system. Normally, the following train would have stopped immediately after confirming that the lights were off, but the driver of the following train was blinded by the direct rays of the sun and was unable to determine that the lights were off. The driver of the following train was not aware that the ATS-B alarm does not stop sounding even if he presses the check button when the signal system is out of order, so he was distracted by the ATS alarm that did not stop sounding and operated the ATS switch to see if it was a malfunction. (It is a regulation that the train should stop immediately when the signal light goes off as a stop sign.)
June 23, 1972 Rear-end collision in Nippori station A northbound Keihin-Tohoku Line train No.1332C (Sakuragicho to Omiya: 103 Series 10-car formation) finished handling passengers at Nippori Station and departed two minutes late, but the door-closing indicator light on the driver’s cab went out, so the train applied the brakes and stopped about 90 meters ahead. On the other hand, the driver of the following Yamanote Line inner bound 1370th train (at that time, the Yamanote Line and the Keihin Tohoku Line were running on the same track between “Tabata and Tamachi” station during the day time for track maintenance. The train departed from Uguisudani station one minute late and was about to enter Nippori station when it noticed a train ahead of it stopped at the middle part of the platform and applied the emergency brake, but it could not brake in time and it hit the train. 143 people were injured. The cause of the collision was that the driver of the Yamanote Line drove faster than the speed limit of the on-board signal system. This accident led to a study of signal security equipment and the decision to convert to ATC on the Keihin Tohoku Line and the Hand Line. However, the implementation of ATC was delayed until December 6, 1981 because of the delay in the preparation of the rolling stock.
December 05, 1988 Chuo Line Higashi-Nakano Station train rear-end collision A down train (Series 103 with 10 cars) from Tsudanuma to Nakano was rear-ended by a down train (Series 201 with 10 cars) from Chiba to Nakano, which was stopped at Higashi-Nakano Station on JR East’s Chuo Loop Line. It was the first fatal accident since the establishment of JR.
September 14, 1992 Narita Line Oosuge level crossing accident At the Oosuge level crossing between Kusumi and Namekawa Stations on JR East’s Narita Line, a regular train (Series 113) bound for Sawara from Chiba collided with the side of a large dump truck that was entering the crossing when the barrier was down. The lead car was derailed and wrecked, killing the train driver and injuring 65 passengers. The driver had prepared for the collision and had taken safety measures such as shutting off the power supply by lowering the pantograph. The cause of the accident was that the dump truck, which was overloaded (it was carrying four times its maximum load of sand), failed to stop because the brakes did not work at the stop line at the level crossing.
October 12, 1997 Chuo Line Otsuki Station train collision At Otsuki Station on the Chuo Main Line, the side of a “Super Azusa No. 13” (E351 Series, 12-car train) limited express train from Shinjuku to Matsumoto, which was passing on the down train line, was hit by a replacement car (201 Series, 6-car train) that had entered the down train line from the waiting line, derailing cars 5 and 9 of the limited express train (car 8 was overturned) and the front two cars of the replacement car, and 77 passengers of the limited express train were injured. Seventy-seven passengers were injured. The cause of the collision is said to be that the driver of the replacement car, after he had released the automatic train stop system (ATS) on his own initiative for the replacement work in the yard, mistook the signal of the departure signal of the down main line for that of the replacement car and overlooked the stop signal of the replacement signal.
February 21, 1999 Yamanote Freight Line worker killed by touching car Five workers of JR East’s construction contractor were carrying materials and equipment for the construction of signal security equipment on the track between Osaki and Ebisu stations on the JR Yamanote Freight Line when they were hit by a special train from Shinagawa to Kobuchisawa (train 9531, EF64 electric locomotive + “Edo” coach: 7 cars in total). All five people were killed. The accident was caused by the following factors: the contractor’s construction supervisor was late to the work site and called the JR Signal Communication Control Room (Kita-ku, Tokyo) to start work without checking the train operation status at the Osaki Station Signal Handling Station; the supervisor allowed workers to enter the track without conducting an on-site roll call (meeting); the train guard was not given a train schedule with information about the extra trains; and the train guard was not given a train schedule for the day. The train guard was also on the opposite side of the track from where the train was coming. 
February 23, 2014 (February 23, 2014) Keihin Tohoku Line train overturned and derailed A derailment accident occurred at around 1:00 a.m. on February 23rd at Kawasaki Station on the JR Keihin Tohoku Line when a train was overturned. The first and second cars of the 10-car train overturned, and the third car tilted about 75 degrees and collided with a trackside truck, which was used for repair work on the tracks. The wrecked cars were No. 9 and No. 10. The E233 Series 1000-177 formation, of which Moha E233-1477 is a part of the formation. It is said that the heavy equipment (9.5-ton rail car) used to transport materials on the tracks was caused by “putting heavy equipment on the Keihin Tohoku Line tracks, mistaking them for another line that had already completed its service”.
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JR East Niigata Branch Niitsu Rolling Stock Works

051s-9 Niitsu Rolling Stock Works is a rolling stock manufacturing plant of JR East located in Niigata Prefecture.
The Niitsu Sharyo Seisakusho has been engaged in remodeling, repairing, and maintenance of rolling stock, but in October 1994, it was reorganized and converted into a new train manufacturing plant, and started manufacturing trains with the technology licensed from Tokyu Sharyo Seisakusho.
The production process starts from the process of processing stainless steel plates, which are the raw materials, and manufactures not only car bodies but also important parts such as bogies.
We have achieved highly efficient production by utilizing CAD/CAM and robots, and our production volume has reached one car per day, with an annual production capacity of 250 cars.
E217 series
An information network has also been established using dedicated lines, connecting the JR East Tokyo, Yokohama, Hachioji, Omiya, and Chiba branches, the Tokyo General Rolling Stock Center, the Nagano General Rolling Stock Center, each rolling stock center, each train section, and our partner Tokyu Car Corporation, to share design information and other information for efficient design and manufacturing.
recipient (of goods, etc.) car model
East Japan Railway Company Series 209, E217, E231, E233, E531
Odakyu Electric Railway Type 4000(4056F) 1 formation 10 cars
Sagami Railway Series 10000/11000
Tokyo Metropolitan Bureau of Transportation Series 10-300 10-450F to 10-470F 18 intermediate cars (3 trains)
058s-7 011s-13 020s-6 013s-16
4056F (manufactured in 2007) Series 10-300 (manufactured in 2010) 10507F (manufactured in 2005) 11903F (manufactured in 2010)
After the completion of the manufactured rolling stock, the company’s own rolling stock will undergo a trial run (official trial run) for several round trips between Niitsu and Niigata Stations on the Shinetsu Main Line. The date of the official test run is set as the completion date.

Tokyo General Rolling Stock Center

041s-11 190s 188s 046s-16
Vehicle Exhibition Series 209 MUE-Train Series 185 OM03 115 series train ride experience
042s-15 043s-11 044s-14 045s-15
E231 Yamanote Line E231 Yamanote Line Series E233 Keihin-Tohoku Line Series E231 Shonan Shinjuku Line
Tokyo General Rolling Stock Center was established on June 1, 2004 by the merger of Yamate Train Depot and Oi Works, and is under the jurisdiction of JR East Tokyo Branch Office. The East Area is where all the E231 Series trains of the Yamanote Line are inspected and refurbished, as well as test cars and commercial cars. The west area is called the west area and has the most suitable inspection facilities for new trains (Series 209, Series E231, Series E233, etc.). The West Wing for the inspection of new rolling stock completed in November 1997 and the East Wing for the inspection of new rolling stock completed in December 2004 are equipped with facilities that enable efficient inspection of bogies, on-roof equipment, etc., while each car is connected in units of 5 cars (West Wing) or 10 cars (East Wing), instead of dividing each car into individual cars.
JR East 2011 Summer Vacation Fair Tokyo General Rolling Stock Center
At the Summer Vacation Fair, which opened to the public on August 27, 2011, the rolling stock on display included Series 209 MUE-Train, Series E233 Chuo Rapid, EF510 Electric, Series 183 Shonan Color, Series 143 Business Car, and Series E217 Yokosuka. The experience and observation corner was held with substantial contents, such as lowering the car body, climbing up and down from a high scaffold, passing through the car body washing equipment, displaying cut models of various parts, riding the Series 115, operating the driver’s cab, and experiencing the conductor using the broadcasting equipment.
049s-8 047s-14 048s-7 050s-14-2
Toyota Rolling Stock Center
053s-12 054s-12-2 The Toyota Sharyo Center was established in 1963 as the Toyota Station Detention Line with a capacity of 40 cars, and in 1965 it became the Toyota Depot of the Musashi Koganei Train Depot with a capacity of 260 cars.
The trains belonging to this section are E233 Series (688 cars) for Chuo Rapid Line, 115 Series (46 cars) for Chuo Main Line, and 189 Series (6 cars) for Chuo Main Line.
060-2 059 062
Toyota Rolling Stock Center Main Building 201 series (KUHA201-1) E233 series
065 064 063
189 series 211 series 115 series
Toyota Rolling Stock Center Festival 2014]
On November 8, 2014, JR East Hachioji Branch held the “Toyota Rolling Stock Center Festival 2014”. It included exhibits of Kuha 201-1, Series 211-1000 N324 formation [Utsunomiya Line direct service (rapid Fuji-Kawaguchiko HM display)], Series 115 C1 formation (553M), Series 189 (N101 formation), EF64 (Unit 39), Series E233, etc., demonstrations of rolling stock maintenance work, and mini Shinkansen operation.
Mitaka Rolling Stock Center
056s-11 055s-15 The Mitaka Rolling Stock Center was established in June 1929 as the Mitaka Branch Office of the Nakano Train Depot, and came under the jurisdiction of the JR Hachioji Branch Office when it was established in April 1998. The number of cars in the train section is 662, including E331 and 209 Series for the Chuo Sobu Line and E231 Series 800 for direct operation on the Tokyo Metro Tozai Line.