World-renowned architect Dominique Perrault unveiled details of an ongoing project at Seoul’s Gangnam Intermodal Transit Center at an exhibition held at the French Embassy in Seoul on Thursday.

The exhibition centers around a newly published book that introduces the history and implications of the transit center at the heart of Seoul, which will become the largest underground station in the world.

“The 'Lightwalk' will bring a change to the history of underground space in Seoul. It will be hard to think of an underground space without light after it. The Lightwalk will mark the city's 'before and after,'” the architect said at the opening of the exhibition, speaking in French with a Korean interpreter.

Perrault and the Seoul-based Junglim Architecture Consoritum won an international competition to design Seoul’s Gangnam Intermodal Transit Center in 2017, an immense subterranean transport hub located in southern Seoul.

The construction of the Lightwalk is expected to be completed in 2028.

The project aims to connect an underground station for two major subway stations, Samseong and Bongeunsa, and three high-speed train lines -- KTX, GTX A and GTX C -- where 600,000 people will travel every day, according to Perrault.

The underground space will feature natural light, as well as an underground park with plants cultivated by both natural and artificial lights. The Lightwalk will also contain public spaces such as a pedestrian-only ground plaza where various activities will be held.

The exhibition features a recently published book which shows the history and details of the project, including design sketches. The pages of the book – which is not commercially on sale – act as the main thread running through the exhibition. The exhibition also includes miniature architectural models of the Lightwalk.

The French architect was widely recognized in South Korea for his design of the Ewha Campus Complex at Ewha Womans University in Seoul, which was completed in 2008 and won the Seoul Metropolitan Architecture Award in the same year.

“The GITC project shares with Ewha’s experience a common spirit: the idea that the future of our metropolises will involve a reinvention of territories through their subsoil and the creation of architectures anchored in their geography,” the architect wrote in the book.

The Lightwalk's total ground floor area will mark a 167,000 square-meter space.

The exhibition will run through Dec. 22 at the French Embassy in Seodaemun-gu, Seoul.