The "International Highway Project," a plan to connect Tokyo to London with a high-speed transportation network, was proposed in November 1981 at the 10th International Conference on the Unification of Science (ICUS) held in Seoul, South Korea.
This concept originally existed as a transcontinental railway during the era of the former Japanese National Railways (Ministry of Railways), and as a massive project crossing national borders, it is also the largest project in human history spanning the 20th and 21st centuries.
Over the past decade, invaluable data has been accumulated through research and investigation.
While Japan has completed major projects such as the Seikan Tunnel and the Seto Ohashi Bridge, this wisdom should not be used solely for the benefit of the Japanese people, but rather for the improvement of the welfare of all humanity. Today, humanity has ended the Cold War and is moving from war to peace, and moreover, we have entered an era of global thinking, with "international contribution" becoming a fundamental principle of Japanese national policy. Looking at the world, European integration has been achieved, and the Dover Channel Tunnel connecting Britain and France has also been completed (open for business in 1994). Now is the time for our country to fulfill humanity's dream of a "Tokyo to London" flight.
First, looking at the effects of the development and the aims of the project, the following are some specific things that can be considered:
By establishing an international order based on the lofty value of love for humanity, we can avoid enormous economic waste and loss of resources.
This will facilitate the exchange of people, goods, and culture (through high-speed transportation systems and communication networks using fiber optic cables, for example), promote the standardization of technology and industry, and contribute to the balanced development of Asia.
This enables the effective use of energy (electricity, etc.) and resources (natural gas, water, etc.).
This would be a major stepping stone towards the formation of an East Asian community (Japan, South Korea, China, and Taiwan have a combined population of 1.4 billion).
The East Asian region has diverse and abundant human and material resources, and by improving transportation infrastructure, it can create a powerful economic zone. In this context, Japan, South Korea, and northeastern China would play a core role as industrialized nations.
It will help revitalize the global economy.
By further improving the technical know-how accumulated through projects such as the Seikan Tunnel, the Honshu-Shikoku Bridge, and the Tokyo Bay Crossing Highway, we will be able to contribute to large-scale projects around the world.
As an example, by connecting not only the Japan-Korea Tunnel but also the Soya Strait and Mamiya Strait with undersea tunnels, it will be possible to realize a transportation network around the Sea of Japan.
The construction of the Japan-Korea Tunnel will create long-term employment and demand for materials, bringing enormous economic benefits to the related regions and helping to stabilize the economy and resolve economic friction.
In Japan, we are developing a new comprehensive plan called the Second National Axis Concept. The intersection of the conventional First National Axis (Tokaido and Sanyo Roads) and the Second National Axis (Tokyo, Ise Bay, Kii Peninsula, Kitan Strait, Shikoku, Bungo Strait, Kumamoto <Nagasaki>) will be in northern Kyushu, and by connecting this point with the Korean Peninsula, we can establish cooperation with the continent. Many projects are planned in the Chugoku, Shikoku, and Kyushu regions, and this east-west domestic axis, when connected with the continent, will intersect with the north-south international axis

*From the Tosu Junction "Saga Prefectural Government Office" website
According to an analysis of transportation trends within Japan , truck transport accounts for the majority of logistics. While air transport handles urgent goods and high-value long-distance items, and sea transport handles bulk cargo, it is expected that trucks will be the primary mode of transport for processed goods in the coming era of horizontal division of labor between Japan and Korea. Similarly, for passenger transport, air transport is dominant for long distances, while rail transport is dominant for distances between 500km and 700km, and automobile transport accounts for the majority within 500km. Centered around the Tosu Interchange , the most important land transportation hub in Kyushu , a 500km radius ( centered on Tsushima in the diagram ) covers almost all of Korea and western Japan. The traffic demand for the Japan-Korea Tunnel, which will run through the center of this circle, will likely consist of rail and container (or truck) transport for logistics and high-speed rail (or automobile) transport for passengers. Furthermore, large-scale projects that will mutually affect the Japan-Korea Tunnel are conceivable within the aforementioned 500km radius. Regarding international highway routes within Japan, future considerations should be made in light of their integration with existing transportation systems and in accordance with new land use practices that align with the lifestyles of the next century (construction has already begun on the Second Tomei and Meishin Expressways). In formulating development plans for the Japan-Korea tunnel-related areas, it is necessary to clarify the roles and functions of each region as a basic principle, while also considering how to enhance international synergies in relation to existing development plans.
Projects aim to have an impact, either domestically or internationally, directly or indirectly. The "Kyushu-Tsushima Strait Tunnel (Bridge)" as a domestic issue is considered one concrete measure to stimulate the culture and economy of Kyushu and other regions along the Sea of Japan. In particular, its purpose is to greatly contribute to resolving the problems of remote islands, including northern Kyushu, Iki, and Tsushima. Remote islands face significant challenges in transportation depending on weather conditions, posing a major source of anxiety for daily life in a broad sense, similar in some respects to the factors behind the Seikan Tunnel project. The
only way to resolve this is to secure a complete transportation route, which can only be achieved through the construction of bridges, underwater tunnels, or other similar measures. As an international issue, the "Tsushima-Korea Strait Tunnel" project envisions creating a cultural, political, and economic ecosystem through mutual solidarity between the continent, the Korean Peninsula, and Japan, stimulating economic activity and improving living conditions in a broad sense, with the expectation of contributing to the construction of lasting peace in East Asia.
The construction project itself will consist of both domestic and bilateral aspects. Regarding undeveloped technologies related to construction, technology transfer should be promoted, and joint ventures may be considered in some cases. The "Kyushu-Tsushima Strait Tunnel (Bridge)" project is a domestic issue for Japan, so it should be approached by gradually seeking a wide range of participants, forming a promotion group, and proceeding under national consensus. The objective is likely to be to connect not only the mainland and the outlying islands, but also Japan and the continent, and to build a community of shared values that protect freedom, human dignity, and the rights of each nation-state.