Seoul reopens a tunnel sealed for 40 years as 'K-Culture Station,' opening with a BIGBANG exhibition

A Tunnel Sealed for 40 Years Gets a Second Life

Thirteen meters beneath Seoul Plaza sits a passage most Seoulites never knew existed. The tunnel connecting City Hall Station and Euljiro 1-ga Station has been closed for more than four decades, and until this week it stayed that way — unlit, unused, forgotten under one of the city's busiest intersections. Seoul's city government has now reopened it as K-Culture Station, a 335-meter cultural space that keeps the tunnel's original industrial bones intact: exposed concrete walls, bare support pillars, none of it smoothed over.

Opening Act: BIGBANG's 20th Anniversary

The venue launched on August 24 with its first show, the BIGBANG 20th Anniversary Media Exhibition "COSMOS," timed to the group's 20th year since debut. The exhibition spreads across 11 immersive zones running the length of the tunnel, mixing projection mapping, holograms, and VR into the walk-through format. It's the kind of programming built specifically for a long, narrow underground corridor rather than a conventional gallery box.

How to Visit

COSMOS runs through September 27, closed Mondays, with hours from 10 a.m. to 10 p.m. (the opening day, August 24, started later at 2 p.m.). Entry costs KRW 20,200 and requires advance reservation through Naver — walk-ins aren't part of the setup. The space operates on an hourly reservation system, admitting 100 visitors per session across 12 sessions a day, so the total daily capacity runs to about 1,200 people. Seoul's city government also posted the announcement on its official Facebook page, alongside matching posts on Instagram and X.

What Comes After COSMOS

K-Culture Station is built to outlast this one exhibition. It's part of Seoul's "Fun Station" project, and once COSMOS closes, the city says the tunnel will keep rotating through collaborative exhibitions with global K-pop artists, K-fashion shows and brand showcases, and pop-up or entertainment-tech experiences. Seoul currently runs three other Fun Stations: Runner Station at Yeouinaru Station, Fit Station at Ttukseom Station, and Smart Move Station at Meokgol Station. Separately, Gwanghwamun, Hoehyeon, and World Cup Stadium stations each have a "Runner Support Space" with changing rooms and lockers — a smaller-scale version of the same idea, turning idle transit infrastructure into something visitors can actually use.

Editor's take

This is Seoul treating unused subway infrastructure as a recurring stage rather than a one-off pop-up site, and that's the detail worth watching. Fun Station and the Runner Support Spaces already show the same instinct — take dead space under a station and give it a second job — so K-Culture Station reads less like a novelty and more like a template the city intends to reuse with different K-pop partners down the line. For overseas visitors, the practical takeaway is timing: COSMOS only runs through September 27, tickets are gated by hourly Naver reservations with a hard cap of 100 people per slot, and there's no walk-in option, so anyone routing a Seoul trip around it needs to book ahead rather than show up and hope. Expect the city to name its next tunnel collaborator once this run wraps.