Notes from Korea: Seoul’s World-Class Transit is Abundant, Cheap, and Integrated

Seoul Station, the country’s largest rail hub, where KTX high speed rail trains depart for Busan and other destinations.

Seoul, South Korea, opened its first metro line, Line 1, in 1974—two years after BART launched its inaugural service in the San Francisco Bay Area in 1972.

Just over fifty years later, the two regions have diverged greatly in public transportation. Greater Seoul has built one of the world’s most extensive and seamlessly integrated public transit systems, with 23 metro lines, over 700 stations, and at least 7,000 buses. High-quality transit connects all parts of the region, anchoring dense, mixed-use communities—and transit travel times are competitive with driving. The Seoul Metropolitan Area boasts a transit mode share of 38%, while cars make up just 30%. In contrast, the San Francisco Bay Area’s transit mode share is about 5%, compared to over 70% for cars.

Transport Mode Share in Seoul Metropolitan Area (Source: International Transport Forum)

Aboard the first phase of GTX-A, which opened in 2024 - deep underground, the express train offers a smooth (and carpeted) ride across greater Seoul, traveling at speeds of up to 180 kilometers per hour.

Despite achieving what would be considered by most to be “world-class transit,” Seoul continues to pursue one of the most ambitious transit expansion programs in the world. Several new metro and light rail lines are under construction, the city is launching a new ferry system, and the super-fast regional Great Train Express (GTX) network, which will connect the entire region like never before, is opening in phases.  Busan, South Korea’s second-largest city, has been rapidly expanding bus rapid transit (BRT) lines and plans its own Busan Express Railway (BuTX) rapid rail network to open by 2030—expanding upon its already impressive existing network of over 150 metro, light rail, and regional rail stations. Numerous studies, such as NYU’s Transit Costs Project, cite South Korea as a model of efficiency for transit capital projects, with some of the lowest transit construction costs in the world.

South Korea’s ambition and track record in building transit are clearly inspiring. I arrived here last week to understand what lessons it could offer California, with support from the Wendy Tao Smart Cities Scholarship and ITS California.

California has no shortage of ambitious goals for transforming transit, but progress has been achingly slow. Most large capital projects take decades to build, and service among the state’s over 300 operators is poorly connected—the transit experience in California falls far short of world-class. While state, regional, and local governments have raised a lot of money through ballot measures, they have largely failed to spend it effectively to deliver transformational benefits. California’s ineffectiveness has begun to undermine public confidence in government’s ability to “do big things.”

In this three-part blog series, I’ll document my experiences and insights from South Korea and explore the lessons it could offer California. In this first post, I’ll provide some context on South Korea and California, as well as my initial impressions of Seoul’s transit as a first-time user. The second post in this series will describe the key reforms from the early 2000s that changed the trajectory of Seoul’s transit, particularly the integration of bus and rail networks and fare integration. Finally, my third post will explore the insight that strong government has been an indisputable component of Seoul and South Korea’s success, and I’ll describe some of the specific ways the country has built government capacity that California could learn from.

Comparing California and South Korea

While no two places are exactly alike, there are plenty of reasons to compare California and South Korea. Both are high-income economies with roughly similar populations—South Korea has 51 million people compared to California’s roughly 40 million. Both are multi-party democracies with a balance of power between the executive, legislative, and judicial branches, and a range of municipal, regional, and central/state governments. Greater Seoul, with a population of about 25 million, is one of the world’s megacities and is comparable in scale to Greater Los Angeles’ roughly 20 million people. The San Francisco Bay Area is roughly as populous as the Busan-Ulsan Area, South Korea’s second-largest region, with about 7 million residents.

South Korea’s  regions are connected by a high-speed rail link that began construction in 1992 and was completed in 2004. While the distance between Seoul and Busan is less than two-thirds of the distance between San Francisco and Los Angeles, the terrain is far more challenging, as the Korean peninsula is highly mountainous.

There are some obvious differences between South Korea and California, with one of the most noticeable being the level of urban density. Seoul is one of the densest cities in the world— a deliberate policy choice shaped by the governments transportation and land use planning—making it far more amenable to high levels of ridership. There are also significant cultural differences, though it is not my place to assume their significance.

Regional train operated by Korail, the national rail company, in Busan.

Nevertheless, I believe many of South Korea’s lessons for California are still applicable, particularly when it comes to best practices for building quality infrastructure and running people-focused services. While South Korea’s higher density makes transit investments more effective, density does not automatically result in the construction of large, complex transit projects—governments still have to build them. In fact, high levels of density can make building new transit projects more costly and complex.

First Impressions: After Getting Over the Learning Curve, Seoul’s Transit is a Breeze

One of the many rectangular versions of the Subway Metro map, which can be quite overwhelming (as well as hard to read), and look completely different from the square version, where the ‘circle line’ (Line 2) appears as an actual circle.

What has my actual experience with transit in South Korea been like over the past week? I’ll be honest: I had some initial challenges figuring out some of the basics. After landing at Seoul’s Incheon Airport, I discovered that the trip-planning tools I’m used to don’t work in Korea, so I was reliant on physical signs to figure out where to go. While I love maps, the gigantic Seoul Area Metro was quite overwhelming—and many versions of it are hard to read.

Area maps and showing the various exits and at Euljiro 4 station.

After following signs for the ‘airport train’ once I cleared security, I was faced with a multitude of ticket machine options, as my foreign credit card alone wasn’t sufficient to enter the train station. I had heard that a T-Money card was the best way to go for transit, as it’s accepted across the country on all agencies and modes, plus it offers a modest discount over individual tickets. However, the T-Money card machine at the airport only accepted cash, which I didn’t have. I ended up purchasing a single-use ticket.

Once I eventually figured out how to pay and enter the system, the Airport Express Train (AREX)—like nearly every metro line I’ve taken since arriving—has been fast, quiet, and spotlessly clean. Platform screen doors at every station reduce noise while waiting for the train. Line diagrams are prominently displayed at all platforms and aboard trains, and real-time screens and announcements in multiple languages make it easy to know your location at any time. Station maps and signs with clearly numbered exits are visible at every station platform, making transfers painless. Most trains arrive every few minutes.

I transferred between multiple transit agencies on several occasions, and the experience was always easy and predictable. My T-Money card (once I finally got one) was accepted everywhere, including on Busan’s transit network. Network maps always show all of the rapid transit lines in the region—not just those run by the operator you're riding.

Bountiful Buses

Bus priority lanes and BRT stop in central Seoul.

Buses are everywhere in Seoul and seamlessly integrated with the metro system in every respect. Since 2004, fares have been fully integrated between the bus and metro systems, using a distance-based fare system. Riders pay one fare for their entire journey based on distance, not the number of transfers (more on this in Part 2 of this series). After overcoming my initial fear of riding the bus and figuring out the right app for trip planning, I found the buses extremely easy to navigate. Not only is a bus often the fastest trip option between two points, but it also provides much more interesting views of the city.

Buses in both Seoul require you to both tap on and tap off in order to calculate your distance-based fare, but base fares are cheap – just ₩1400, or just under US$1 for trips under 10 km in Seoul, and an additional  ₩100 for each additional 5 km. In Busan, fares are a flat rate of ₩1550. 

Dedicated bus lanes and complete “BRT” treatment for buses in downtown Busan.

Dedicated bus lanes are provided on many of the busiest urban streets, and large, expansive bus shelters are provided for waiting passengers. Major bus stops have multiple numbered ‘platforms’ so several buses can offload and board passengers simultaneously. Huge real-time screens show the upcoming arrivals for dozens of lines. I’ve never waited more than a couple of minutes for a bus. Some bus shelters even feature heated seating and free wireless phone charging.

Some room for improvement; nevertheless, it’s a system you can trust

Of course, no system is perfect. Not all streets have dedicated bus lanes, so on more than one occasion I was stuck on a slow bus amidst a sea of cars in Seoul’s brutal traffic. Seoul also has many very wide arterial roads, making for an occasionally uncomfortable pedestrian experience.

Subway entrance with the standard Seoul Metro Identification sign; “4” indicates the exit, not the line number.

I also noticed significant variation in transit signage, which seemed to communicate a lack of system-level organization when, in fact, the system is highly connected and logically structured. The line naming conventions were somewhat confusing to me—only about half the metro lines are numbered (including both Seoul Metro’s Lines 1-9, in addition to Incheon Metro’s Lines 1 and 2), some lines have names, and others use acronyms.  The colors can be hard to distinguish.

Fortunately it appears that many of these signage consistency issues are will get resolved over time with updates to standards and recently announced unified branding across modes.  And after just a few days of riding, I have learned I can generally trust the system, even if some of the naming and signage conventions are a bit confusing.

In short, the fundamentals of transit service are excellent – service is frequent and fast, connections between modes and lines are seamless, passenger facilities like bus shelters are superb, and fares are cheap and predictable.

So, how did the system get this way, and what can California learn? I’ll dive in that in my next two posts.

Ian Griffiths