Gwangju's 800-trillion-won semiconductor hub takes shape — but its rail link remains a bottleneck

As plans advance to build a large-scale semiconductor production complex on the site of Gwangju's military airport, concerns are mounting that the rail network meant to support it could become a chokepoint. Calls are growing for the Gwangju Songjeong–Suncheon segment of the Gyeongjeon Line — currently planned as a single-track railway — to be upgraded to double-track, given the expected surge in passenger and freight demand once the semiconductor industry comes online.

According to industry sources Friday, the Gwangju Songjeong–Suncheon rail construction project is being developed as a roughly 121-kilometer single-track electrified line. The core concern is that this segment would be the only single-track stretch along the entire Gyeongjeon Line, which runs from Gwangju Songjeong through Boseong and Suncheon to Jinju and Busan. Sections east of Suncheon into the Yeongnam region have already been double-tracked, leading experts to warn that the Gwangju Songjeong–Suncheon segment could become a long-term bottleneck constraining the line's overall capacity.

A dramatic shift in the industrial landscape around Gwangju has also revived the double-tracking debate. The government and private companies have unveiled plans to invest 800 trillion won ($574 billion) in the Honam region to build four memory chip fabrication plants, and the Gwangju military airport site — spanning roughly 8.25 million square meters — has been designated as the location for a semiconductor industrial complex.

Once semiconductor production facilities begin full operation, the Gyeongjeon Line's role could expand well beyond its current passenger focus to serve as an industrial and logistics corridor. Finished semiconductor products are largely shipped by air, but the heavy manufacturing equipment, materials and components needed to build and maintain production lines are continuously brought in via ports and overland transport networks. The Gyeongjeon Line's role in connecting the port and manufacturing base of Busan and South Gyeongsang Province with Gwangju and South Jeolla Province could therefore grow considerably.

A single-track line has inherent limits on how many trains can run, since inbound and outbound services share the same rails. If KTX and regular train services increase while freight demand from industrial activity is added on top, a shortage of track capacity could become a real problem. Analysts say planners need to factor in not only the Honam semiconductor cluster but also the AI industry, the Yeosu national industrial complex and tourism demand along the southern coast.

Passenger demand at Gwangju Songjeong Station itself is also expected to rise. When integrated KTX and SRT operations launch in September, train services and seat supply on the Honam Line will increase, and new high-speed rolling stock is scheduled for introduction from 2027.

Rising raw material prices, labor costs and land compensation expenses add another layer of complexity. If growing demand eventually makes double-tracking unavoidable, retrofitting the line after it opens as single-track would cost far more in the long run than reassessing track capacity now, at the design stage.

"If you try to double-track a line after it has already opened as single-track, you may have to acquire additional land and pay compensation all over again," a railway industry official said. "You would need to expand tunnels and bridges alongside the existing track or install separate structures — and all of that construction would have to proceed while trains are still running, which significantly raises both the difficulty of the work and the safety management burden."

"Rail infrastructure, once built, serves the nation for decades, so it is hard to make decisions based solely on immediate demand," the official added. "The double-tracking question needs to be examined with an eye on the medium- and long-term passenger and freight demand that will grow as Gwangju's semiconductor fabs and surrounding industrial complexes take shape."