In this blog post, we will focus on Balhae’s capital city and Sejong City to explore how Korea’s planned cities can influence global urban design.
Have you ever heard of “Balhae’s capital city”? The name “capital city” may sound unfamiliar, but Balhae, an ancient kingdom that flourished from the 8th to the early 10th century across northern Korea and Manchuria, is a name that anyone interested in world history or East Asian history would have heard of at least once. Balhae was founded in 698 by Dae Jo-yeong, a descendant of the Goguryeo kingdom, and boasted a high level of cultural exchange with China, Japan, and the Arab world. Among its cities, Sanggyeongseong served as the third and final capital of Balhae, functioning as the nation’s central hub for approximately 160 years and experiencing a period of dazzling cultural prosperity.
Sanggyeongseong was laid out in a grid pattern centered on the inner city, with a large road called “Jujak-daero” running through the center. This road stretched northward from the south gate of the imperial palace, measuring an impressive 2.2 kilometers in length and 110 meters in width, making it quite grand for its time. This road, which had more than just a transportation function, is a representative example of the systematic urban planning of the state.
Balhae had a clear purpose in constructing a large grid-shaped road network and the Jujakdaero in Sanggyeongseong. First, it was to enable the rapid movement of supplies and troops in preparation for external turmoil, such as the An Shi Rebellion that occurred in the mid-Tang Dynasty (late 8th century) in China. Second, it also had a political purpose of symbolically demonstrating the authority and order of the monarchy through the main road centered on the royal palace. In other words, Sanggyeongseong was not just an administrative hub, but a city designed according to a thorough plan.
A city designed systematically to achieve specific purposes is called a **“planned city.”** Planned cities differ from traditional cities, which expanded naturally over time. For example, traditional cities grow gradually in response to population growth or economic needs, but planned cities strategically arrange various elements such as transportation, housing, environment, security, and administration by considering urban functions in advance, demonstrating the foundation of modern urban engineering. Representative planned cities in South Korea include Changwon and Ilsan, which were developed in the 1980s and 1990s, and more recently, **Sejong Special Self-Governing City (Sejong City)**, which has emerged as the administrative capital of South Korea, has been gaining global attention.
Sejong City is an administrative complex city located in the central part of South Korea, designed to alleviate overpopulation in the capital region and promote balanced national development. So, did Sejong City also follow the grid-shaped road structure of Balhae’s capital city? While it may appear similar to traditional urban design at first glance, a significantly different approach was actually adopted. Grid-shaped roads have numerous intersections, which can cause traffic congestion, and expanding roads poses a high risk of environmental damage. Additionally, they have low connectivity between land areas and limitations in resident communication. For these reasons, Sejong City abandoned the traditional grid-shaped design and opted for a more efficient and sustainable urban structure.
The structure adopted by Sejong City is the **“double ring-shaped urban structure.”** Traditional ring-shaped cities focus on placing circular roads around the city’s periphery to facilitate smooth vehicle flow and preserve central urban functions. In contrast, Sejong City’s double-ring structure is an evolved form that distributes urban functions around two circular rings, with green belts and public spaces in between, aiming to achieve both environmental conservation and improved quality of life for citizens. The inner ring is mainly composed of parks and green spaces, providing citizens with rest and relaxation, while the outer ring is planned with administrative, residential, and commercial areas along a public transportation axis, achieving efficient land use and functional dispersion. This design also contributes significantly to the creation of a human-centered urban environment and the enhancement of community cohesion.
Urban engineering goes beyond simple architectural design, serving as a practical discipline aimed at optimizing urban functions and addressing societal challenges. Urban engineering plays a key role in improving the quality of human life in various areas, such as improving transportation systems, energy efficiency, securing green spaces, and enhancing the quality of residential environments. In particular, as issues arising from industrialization and urbanization have become prominent worldwide, urban engineering is playing an essential role in resolving the environmental and social crises facing modern society. This is a common challenge not only for Korea but also for countries around the world.
Furthermore, today’s urban engineering is entering a new phase in combination with the concept of “smart cities.” A smart city is a city that utilizes information and communication technology (ICT) to automate and optimize urban transportation, energy, environment, public safety, and administration, and is a future-oriented model that improves both the efficiency of urban operations and the quality of life for citizens. Sejong City is also actively adopting the smart city concept, integrating various cutting-edge technologies such as autonomous public transportation systems, real-time energy and environmental monitoring, and digital administrative services into its urban operations. These efforts go beyond mere technological advancement, representing a new urban paradigm aimed at achieving both environmental sustainability and enhanced urban competitiveness.
As such, urban engineering holds value beyond mere “urban design.” It is a creative and integrated approach to designing the future and improving the quality of life. As it is an area that requires the organic combination of various fields such as architecture, environment, technology, administration, and sociology, urban engineering is inherently interdisciplinary and convergent. And it is precisely at this point that the reason why Korean cities are gaining attention as global testing grounds becomes clear. The philosophy of planned cities, which began with the capital city of Balhae, has evolved further in Sejong City today and serves as a precedent and inspiration for cities around the world moving toward smart cities.
Cities are constantly evolving. And ultimately, it is urban engineering for people that designs and leads this evolution.
