1. What Kind of Space Was Created When Railway Tracks Were Raised?
When railway tracks are laid flat across a city, they block roads and split neighborhoods in two. To solve this, tracks are lifted onto elevated structures. This creates a long, narrow space directly underneath the rails. This area is known as the "space under the viaduct."
In the section between Shimbashi and Yurakucho stations, a viaduct built with brick arches began operation in 1910. Today, the space beneath this 300 m (about 0.2 miles) stretch is being developed by JR Central and JR East. In 2019, the two companies announced a plan for their group companies to operate this area [1].
The total space created in this section is about 10,000 m² (107,639 sq ft) for both companies combined. This is equal to the area of a square that is 100 m (328 ft) on each side. However, this is a combined figure. The portion developed specifically by JR East is reported to be about 8,600 m² (92,569 sq ft) [1].
Who were the first people to open shops in this newly created space?
2. Why Did Shopkeepers Who Lost Their Places Move Under the Tracks?
According to an account found in Wikipedia, a man named Zenemon Iwasaki opened an oden (a type of Japanese stew) shop in Asakusa in 1920. However, he was displaced by the Great Kanto Earthquake. It is said that he moved his shop to the space under a railway bridge because it did not require a "key money" fee [5].
Key money is a lump sum paid to a landlord at the start of a lease, separate from the monthly rent. For a shopkeeper who had just been displaced and had little cash on hand, a location that did not require this fee would have been a significant help. The account also states that his shop became popular as a place to eat cheaply late into the night [5].
It is important to note that the source does not specify that he moved to Yurakucho, so the exact location of his new shop cannot be confirmed. Additionally, the same source claims that the "First Yurakucho Bridge," built between Yurakucho and Shimbashi in 1910, was the first elevated structure in Japan designed specifically to have shops underneath it. However, because this claim has not been verified by primary sources, it should be treated as a statement that "is said to be" the case [5].
3. Does the Law Treat Shops Under Tracks as "Houses"?
As the number of shops increased, legal questions arose about how to classify them. According to Wikipedia, the Tokyo Prefecture government once treated shops under railway bridges as "houses" and imposed a house tax on them. The shop owners sued the prefectural governor in an administrative lawsuit but lost the case [5].
In this case, the shops under the tracks were treated as houses for tax purposes. This information is based on descriptions found in the encyclopedia [5].
Even if the location was recognized as a place for business, trains were still running overhead. How did they manage the noise and vibrations?
4. How Is Noise from Trains Overhead Reduced for Shops Below?
Noise under elevated tracks is generally divided into two types. One is sound that travels through the air. The other is "structure-borne noise," which occurs when vibrations from the train travel through the elevated structure and emerge as sound from the ceiling or other surfaces [6].
Structure-borne noise is somewhat similar to the way ripples spread on the surface of water when you tap a glass. However, the elevated structure is much more complex, so this analogy is only a rough image of how the vibration travels.
JR East has developed technologies to address structure-borne noise. These include "suspended structures" for ceilings and "floating floor structures" [6]. While these measures help manage noise, the use of the space under tracks is not limited to just shops. How has its use changed over time?
5. How Has Space Under Elevated Railways Been Used, from Factories to Daycares?
Research from Nihon University states that the use of space under elevated railways in Japan has a history of over 100 years, and its functions have changed with the times [2]. In Tokyo’s urban lines, significant changes occurred between 1965 and 1985. Some sections shifted from factories to the food and beverage industry. Other sections saw an increase in warehouses, offices, and retail stores like electronics shops [2].
Another study lists various uses for the space under tracks, including police boxes, daycares, community halls, parks, hotels, sports facilities, commercial spaces, and housing [3].
Manseibashi Station opened in 1912 and suspended operations in 1943. Its brick arch viaduct was renovated as a commercial facility in 2013 [7]. Note that this information is based on a summary of search results.
6. How Do Railway Companies Use the Space Under Tracks Today?
The space under elevated tracks is primarily utilized by the railway companies that own them. Research from Nihon University notes that development is active in the metropolitan area but difficult in regional cities where profits are harder to generate [3]. For example, at Gifu Station, the city, the prefecture, and JR Central each placed facilities in the space under the tracks [3].
Tokyu Corporation opened Nakameguro Koukashita in 2016. It includes 28 shops for food, goods, and offices, spanning about 700 m (0.4 miles) [4]. Tokyu’s company history explains that the goal was not merely to rent out space, but to use the asset to enhance the value of the towns along the railway line [4].
Nihon University research also states that the Ministry of Land, Infrastructure, Transport and Tourism created "Guidelines for Town Planning Along Railway Lines" in 2015, which helped advance the development of under-track spaces that had previously had few uses [2]. This guideline is mentioned as a description within the academic paper.
For the first shopkeepers, the space under a railway bridge that required no key money was a significant help. For today’s railway companies, it is a place to create charm in the town. The same space has been given different roles in different eras.
7. How Can You Explore the Space Under Elevated Tracks in Your Town?
Look at a station map or a map at home to find what exists under the elevated tracks near a station close to you. You might find not just restaurants, but also bicycle parking areas, community halls, or daycares. It is interesting to think about which era’s use of the space each example resembles.
If you can go outside, observe from the road to see if there are any special designs in the ceiling or walls of the space under the tracks. Stay on the road and observe from there; do not go near the tracks.
If you want to learn more, you can read announcements from railway companies or papers from Nihon University’s academic conferences to see in detail how the use of space under tracks has changed over time [2].